each group rearrested in the first hour after cardiopulmonary resuscitation, both developing VP, which was converted into a stable rhythm after 2 direct-current shocks of 200 and 300 J, respectively.
Early delivery of defibrillation is most important for successfulresuscitation of patients with VF. If VF is still presentafter the third shock,epinephrine is recommended to increase coronary perfusion pressure and hence myocardial blood flow, in order to achievea better basis for defibrillation and restoration of spontaneouscirculation.’ A number of vasopressoragents for improving myocardial oxygen delivery during cardiopulmonary resuscitation have been tested in animal experiments.4 Studies comparing epinephrine and norepinephrine in pigs suggest that improvement in myocardial hemodynamics appearsto occur when ,82agonist properties are lackjng or minimal.3 We showed,in pigs with VF, that, for restoration of spontaneouscirculation, norepinephrine was effective in a significantly shorter time than was epinephrine.6Epinephrine and norepinephrine in a dose of 1 mg led to the same increase in coronary perfusion pressure.In our investigation, defibrillation after norepinephrine administration led to a higher resuscitationsuccessrate than after epinephrine. As observedin animal experiments,norepinephrine led to a higher incidence of ventricular dysrhythmias requiring lidqcaine treatment in the first minutes after resumption of spontaneouscirculation.4 Rearrest frequency was not different between the groups. This may also have been influenced by lidoCainetreatment.
Transcatheter Laser-Assisted Pulmonic Valve Atresia
Certain limitations must be taken into consideration when interpreting this study. The equipressor dose of epinephrbe and norepinephrineduring cardiopulmonary resuscitation in humans is not known. We do not know whether we would have achievedthe sameresults with a different doseof epinephrine or norepinephrine. Because no previous blinded investigation of norepinephrine for resuscitation of the fibrillating human heart is available, we used only 1 norepinephrine dose in our algorithm. Furthermore, nothing is known about the pharmacokinetics of repeatednorepinephrjne administration during cardiopulmonary resuscitation in humans and the possibility of severecardiac dysrhythmias in the immediate phase after resuscitation. We conclude that the use of norepinephrinein the treatment of VF may be superior to epinephrine, but the optimal doseand the time interval for repeated administration have yet to be determined. 1. Anon. Standardsand guidelinesfor cardiopulmonary resuscitationand emergency cardiac care. JAMA 1986;255:2905-2989, 2. Lindner KH, Ahnefeld FW, SchuermannW, Bowdler IM. Epinephrineand norepinephrinein cardiopulmonary resuscitation.Effects on myocardial oxygen delivery and consumption.Chest 1990;97:1458-1462. 3. RobinsonLA, Brown CG, JenkinsJ, Van Ligten PF, Werman HA, Asthon J, Hamlin RL. The effect of norepinephrineversusepinephrineon myocardial hemodynamicsduring CPR. Ann Emerg Med 1989;18:336-340. 4. Brown CG, Werman HA. Adrenergic agonistsduring cardiopulmonary resuscitation Resuscitation 1990;19:1-16. 5. Smetana J, Racenberg E, Juna S, Markalous P. Resuscitationof the heart, experimental study and clinical experience.Rev Czech Med 1961;7:65-86. 6. Lindner KH, Ahnefeld FW. Comparisonof epinephrineand norepinephrinein the treatment of asphyxial or fibrillatory cardiac arrest in a porcine model. Ciit Care Med 1989;17:437-441.
Balloon Pulmonary
Valve Dilation in
Shakeel A. Qureshi, MB, MRCP, Eric RoSenthaI, MD, Michael Tynan, MD, Rui Anjos, MD, and Edward J. Baker, MD n patients with pulmonary atresia (with or without a ventricular septal defect), a series of operations are Irequired to achievecomplete repair. Theseoften include
Transcatheter laser-assisted pulmonic valve dilation was attempted for pulmonic valve atresia in 5 children aged between 5 dhys and 2 years (Table I). All had an initial systemicto pulmonary artery shunt, followed by pulmonic value atresia, with confluent central pulmoa pulmonary valvototiy or a patch or a conduit to estab- nary arteries: 2 had an associated ventricular septal delish right ventricle to pulmonary artery continuity, and by fect (patients 1 and 2) and 3 had an intact ventricular closure of the shunt and correction of any other defects. septum (patients 3 to 5). Inpatient 1, the centralpulmoWith the advent of newer interventional techniques,a nary arteries were also supplied by major aortopulmo-
number of congenital anomalies can be treated without surgery. Until now, pulmonic valve atresia was considered to lie beyond the scopeof such interventional transcatheter treatment, becauseof the inability to perforate the atretic valve safely. We report our initial experience of transcatheter laser-assistedpulmonic valve dilation in 5 children with pulmonic valve atresia. From the Department of Paediatric Cardiology, Guy’s Hospital, London SE1 9RT, United Kingdom. Manuscript received July 9, 1990; revised manuscript received October 19, 1990, and accepted October 20.
428
THE AMERICAN
JOURNAL
OF CARDIOLOGY
VOLUME
67
TABLE Pt. No.
I Clinical Data
Age
Weight (kg) & Sex
1
2 W)
9.1/M
2 3 4 5
2 (wk) 3 (day) 10 (wk) 40 (wk)
3.3/M 2.1/F 3.2/M 6.7/M
Diagnosis
Prior Surgery
Laser Route
Balloon Size (mm)
PVA.VSD PVA, VSD PVA, PDA PVA, PDA PVA
RBTs LBTs 0 0 LBTs
RV BTs RV RV BTs
35.7 5.7 3,5 3.v.7
LBTs = left &lock-Taussig shunt; PDA = patent ductus arteriosus; PVA = pulmonic valve atresla; RBTs = right Blalock-Tausslg shunt: RV = right ventricle: VSD = ventrlcular Sept.4 defect.
nary collateral arteries. A modified right Blalock-Taussig shunt with a 6-mm graft had been performed when patient 1 was aged 17 months. Patient 2 underwent a modified left Blalock-Taussigshunt with a 5-mm graft. In patients 3 and 4, the right ventricle was hypoplastic and both patients were dependent on the ductus arteriosus. Patient 5 also had a hypoplastic right ventricle and had a modified left Blalock-Taussig shunt with a 5-mm graft when he was 2 days old. When he was 10 months old, he developed increasing cyanosis, hepatomegaly and ascites because of a restrictive foramen ovale that resulted in a dilated right atrium and a moderatepericardial effusion. Cardiac catheterization was performed percutaneously by the femoral venous and arterial routes under general anesthesia in all patients, Usually a 5 or 6Fr multipurpose catheter was inserted through the venous sheath and a 5Fr multipurpose catheter through the arterial sheath. Angiography was performed in the right ventricular body or infundibulum, in the anteroposterior and lateral projections through the venous catheter. The arterial catheter was positioned in the main pulmonary artery through the Blalock-Taussig shunts in 3 patients and through the ductus arteriosus in 2. Angiography was performed in the pulmonary artery in the same projections. The pulmonary valve ring diameter was measured angiographically. In each patient, the venous and arterial catheters werepositioned close to the valve: 1 was used to pass the laser guidewire and the other was used as a landmark. The laser wire consisted of a 0.018-inch TeflonTM-coated guidewire, containing a 116qm optical Jiber and terminating in a 0.5-mm metal tip. The optical fiber was interfaced with a Nd-YAG laser generator (Cardiolase 4000, Trimedyne Inc., Santa Ana, California). In 3 patients (nos. 1, 3 and 4), the laser wire was introduced anterogradely and in 2 (nos. 2 and 5) retrogradely. The laser wire was passed a few millimeters beyond the catheter tip until it was in contact with the valve. The laser energy was delivered continuously at 3.5 Was the wire was advanced across the valve. Once the
laser wire was across the valve, a predilating catheter was passed over it, and this was followed by serial dilation of the valve using appropriately sized balloons far the pulmonary valve anulus (Table Z). Figures 1 and 2 show some of the details inpatients 3 and 5, respectively. In patient 4, the laser wire did not cross the valve and entered the pericardial cavity. No further attempts were made to cross the valve. Successful laser-assisted pulmonic valve dilation was accomplished in 4 patients (nos. 1, 2, 3 and 5) in whom the laser wire crossed the valve after delivery of energy for 3 to 5 seconds. The duration of the procedure was 3.5 to 5 hours. There was an increase in pulmonary artery pressure or a decrease in right ventricular pressure, with little change in systemic arterial pressure (Table ZZ). Afterward, patients I,2 and 5 were ventilated in the intensive care unit for 1 to 3 days before being returned to the ward. Patient 1 was discharged aftef 2 days, patient 2 after 10 days and patient 5 after 2 weeks. Inpatient 3, shortly after the laser wire was snared in the descending aorta, cardiac tamponade developed, which responded to percutaneous needle pericardiocentesis. After hemodynamic stability had returned, dilation with balloon catheters was achieved uneventfully. Two days later, the arterial duct had become smaller, despite continuation of prostaglandin infusion, and balloon dilation of the duct was therefore performed with a 3.5-mm balloon catheter. Patient 3 was extubated 15 days later. In patient 4; who had coexistent infundibular atresia, the laser wire passed into the pericardium from the infundibulum and caused immediate cardiac tamponade, which responded to needle aspiration. After hemodynamic stability was achieved, this patient underwent a systemic to pulmonary artery shunt operation, but died on the operating table. During a short 2- to 6-month follow-up of the 4 successful patients, the Doppler-estimated pressure drop across the right ventricular outflow ranged between 50 and 70 mm Hg, and there was evidence of pulmonary regurgitation in all patients. In patient 5, the pericardial
FIGURE 1. RiiM ventricular angiogram in the left lateral pro&tion showing pulmonic Qalve atresia. Catheter positioned in the main pulmonary artery has been passed through the arterial duct (Ieft). In the middle panel, the laser wire has b&n advanced across the pulmonary valve through the right ventricular catheter. Alter balloon dilation, right ventricular angiogram (right) shotis anterograde ttow across the pidmonary valve.
THE AMERICAN JOURNAL OF CARDIOLOGY FEBRUARY 15, 1991
429
FIGURE 2. Right ventricular angiogram (left) and angbgram in the main pulmonary artery (middle) detins the landmarks. laser-assisted pulmonary valve dilation, right ventricular angiogram (right) shows forward flow into the pulmonary artery.
effusion and ascites resolved. Transcutaneous oxygen saturations in the 4patients rangedfrom 70 to 87% and, in patient 3, the ductus arteriosus had closed. The first cardiac laser application was for an intraoperative pulmonary valvotomy in 1974.l Since then, several investigators have evaluatedthe technique experimentally,2,3but not clinically in children. In adults, bare fiber laser and “hot tip” laser thermal probeshavebeenusedto recanalizeperipheral artery occlusionswith variable success.4,5 In patients with pulmonary atresia and an intact ventricular septum,the hospital mortality for palliative operations (shunt with or without valvotomy) is approximately 1O%.6Some patients may require further palliative operations, either during the sameadmissionor over the next few years. Tbe subsequentdefinitive repair may have a hospital mortality rate of 25 to 50%.6In patients with pulmonary atresia associatedwith a ventricular septal defect, major aortopulmonary collateral arteries and confluent central pulmonary arteries, a staged surgical approach is frequently required in order to achieve a complete repair. The lo-year survival rate in the series reported by Kirklin et al7 was 69% in this group of patients. TABLE II Pressures (mm Hg) Before and After Pulmonic Valve Dilation
Pt. No. 1 2 3 4 5
Right Ventricle(s)
Pulmonary Artery (s/d)
Aorta (s/d)
Pre
Post
Pre
Post
Pre
Post
105
110 100 85 * 90
17/12 21/17 60/25 22/7
36/16 45/15 60/25 * 26/20
106/43 loo/55 go/27 110/40 96/34
115/45 96/50 85/25 * go/40
120 135 115 190
15/11
* Unsuccessful valve dilation. d = end diastok; s = peak systole.
430
THE AMERICAN JOURNAL OF CARDIOLOGY VOLUME 67
After
In this small preliminary series,our initial objective was to determine whether laser-assistedvalve dilation could establish anterograde flow acrossthe atretic pulmanic valves. In the long term, we need to establish whether the right ventricle and pulmonary artery will increasein size. Someof our initial patients had already undergonepalliative shunts,and their outflow tract anatomy was consideredsuitable for the future creation of surgical right ventricular to pulmonary artery continuity. In our first 2 patients, having established anterograde flow across the pulmonary valve, we hoped to achieve closureof the ventricular septaldefectwithout an interim operation on the right ventricular outflow tract. Thus, we wereencouragedto attempt laser-assistedpulmonic valve dilation and dilation of the ductus arteriosus in order to avoid any palliative surgery in patients with pulmonary atresia and an intact ventricular septum. Patient 3 has thus far avoidedany form of palliative surgery and we are monitoring her right ventricular function. Although patient 5 had a surgical shunt establishedin the neonatal period, this patient may likewise not needfurther operations, as the shunt could be occludednonsurgically when indicated. In retrospect,we feel that patient 4 wasunsuitable for laser-assistedpulmonic valve dilation, becauseof the combination of infundibular and pulmonic valve atresia. This reducedthe safety margin when the laser guidewire was directed toward the pulmonary artery. We believethat our first objective of establishinganterograde flow across the pulmonic valve has been achievedand that laser-assistedvalve dilation is feasible in neonates,infants and children with pulmonic valve atresia. However, it should be avoidedin thosewith associated infundibular atresia. Further follow-up is needed to determine whether our long-term objectives can be achieved by this approach. Acknowledgment: We thank Trimedyne Inc. for providing us with the laser guidewires, Paul V. L. Curry, MD, of Guy’s Hospital, and David C. Cumberland, MD, of Northern General Hospital, Sheffield, United King-
dom, for their helpful advice, and Deo Persaud, Cordis, United Kingdom, for providing technical assistance.
1. Arapov AD, Vishnerskii AA Jr, Abdullaev FZ, Korchagin VA, Mirtskhulava KA, Sorgin ME. A preliminary report on laser application in cardiosurgery. Eksp Khir Anesteziol 1914;4:10-12. 2. Macruz R, Martins JRM, Tupinnamba HS, Lopes EA, Varbas H, Penna AF, Carvalho VB, Armelin E, Decourt LV. Possibilidades terapeuticas do raio laser em ateromas. Arq Bras Cardiol 1980;34:9-12. 3. Riemenschneider TA, Lee G, Ikeda RM, Bommer WJ, Stobbe D, Ogata C, Rebeck K, Reis RL, Mason DT. Laser irradiation of congenital heart disease:
potential for palliation and correction of intracardiac and intravascular defects. Am Heart J 1983;106:1389-1393. 4. Ginsburg R, Wexler L, Mitchell RS, Proffit D. Percutaneous transluminal laser angioplasty for treatment of peripheral vascular disease. Clinical experience with 16 patients. Radiology 1985;156:619-624. 8. Sanborn TA, Cumberland DC, Welsh CL, Greenfield AJ, Guben JK. Percutaneous laser thermal angioplasty: initial results and 1 year follow-up in 129 femoropopliteal lesions. Radiology 1988;168:121-125. 6. Kirklin JW, Barratt-Boyes BG. Cardiac surgery. New York: John Wiley, 1986:821-856. 7. Kirklin JW, Blackstone EH, Shimaznki Y, Maehara T, Pacific0 AD, Kirklin JK, Bargeron LM Jr. Survival, functional status, and reoperations after repair of tetralogy of Fallot with pulmonary atresia. J The-m Cardiovasc Surg 1988; 96:102-116.
Atherectomy of Right Coronary Ostial Stenoses: Initial and LongTerm Results, Technical Features and Histologic Findings Jeffrey J. Popma, MD, Ronald J. L. Dick, MBBS, Christian C. Haudenschild, MD, Eric J. Topol, MD, and Stephen G. Ellis, MD oronary angioplasty of lesions involving the right coronary ostium has been limited by suboptimal early successand by high rates of both acute complications and late restenosis.’In nonostial stenoses,directional coronary atherectomy appearsto result in larger residual coronary dimensionsthan doescoronary angioplasty2 and may provide a potentially improved long-term outcome.To determine the immediate and long-term angiographic results of directional atherectomy in patients with right ostial stenoses,we attempted this procedurein 7 consecutive patients with coronary stenoseswithin 3 mm of the right coronary ostium. c
isfactory angiographic result was obtained. Patients were monitoredfor evidence of abrupt closure and intravascular sheaths were removed within 12 hours. Successful atherectomy was defined as a 50% in diameter within 3 mm of the orifice of the right coronary artery.’ After informed consent and pretreatment with aspirin, a calcium antagonist and 10,000 to 15,000 U of intravenous heparin, a 9.5 to 1I Fr guiding catheter (Devicesfor Vascular Intervention, Inc., Redwood City, California) was advanced to the right coronary ostium. A O.Oll-inch coronary guidewire was positioned across the coronary stenosis andpredilation performed with an undersized standard angioplasty balloon (Figure 1). A 5 to 7Fr atherectomy device (Devices for Vascular Intervention, Inc.) was then positioned across the right coronary ostium and the guiding catheter was withdrawn into the ascending aorta. Coronary atherectomy was then performed by the method previously described3 until a satFrom the Department of Internal Medicine, Division of Cardiology BlF245, University of Michigan Medical Center, 1500 E. Medical Center Drive, Ann Arbor, Michigan 48109-0022, and the Cardiovascular Research Laboratory, Mallory Institute of Pathology, Boston College, Boston, Massachusetts. Manuscript received September 17, 1990; revised manuscript received and accepted October 25, 1990.
FIGURE 1. Top left, left anterior oblique projection of a right coronary ostial lesion. Note streaming artifact from inability to fill the distal vessel adequately. Top right, after predilation with an undersized balloon catheter, the atherectomy device is positioned in the coronary ostium and the guiding catheter is withdrawn slightly (lower leff). The coronary ostiim is widely patent immediately after coronary atherectomy (rower rightJ.
THE AMERICAN JOURNAL OF CARDIOLOGY FEBRUARY 15, 1991
431
Early delivery of defibrillation is most important for successfulresuscitation of patients with VF. If VF is still presentafter the third shock,epinephrine is recommended to increase coronary perfusion pressure and hence myocardial blood flow, in order to achievea better basis for defibrillation and restoration of spontaneouscirculation.’ A number of vasopressoragents for improving myocardial oxygen delivery during cardiopulmonary resuscitation have been tested in animal experiments.4 Studies comparing epinephrine and norepinephrine in pigs suggest that improvement in myocardial hemodynamics appearsto occur when ,82agonist properties are lackjng or minimal.3 We showed,in pigs with VF, that, for restoration of spontaneouscirculation, norepinephrine was effective in a significantly shorter time than was epinephrine.6Epinephrine and norepinephrine in a dose of 1 mg led to the same increase in coronary perfusion pressure.In our investigation, defibrillation after norepinephrine administration led to a higher resuscitationsuccessrate than after epinephrine. As observedin animal experiments,norepinephrine led to a higher incidence of ventricular dysrhythmias requiring lidqcaine treatment in the first minutes after resumption of spontaneouscirculation.4 Rearrest frequency was not different between the groups. This may also have been influenced by lidoCainetreatment.
Transcatheter Laser-Assisted Pulmonic Valve Atresia
Certain limitations must be taken into consideration when interpreting this study. The equipressor dose of epinephrbe and norepinephrineduring cardiopulmonary resuscitation in humans is not known. We do not know whether we would have achievedthe sameresults with a different doseof epinephrine or norepinephrine. Because no previous blinded investigation of norepinephrine for resuscitation of the fibrillating human heart is available, we used only 1 norepinephrine dose in our algorithm. Furthermore, nothing is known about the pharmacokinetics of repeatednorepinephrjne administration during cardiopulmonary resuscitation in humans and the possibility of severecardiac dysrhythmias in the immediate phase after resuscitation. We conclude that the use of norepinephrinein the treatment of VF may be superior to epinephrine, but the optimal doseand the time interval for repeated administration have yet to be determined. 1. Anon. Standardsand guidelinesfor cardiopulmonary resuscitationand emergency cardiac care. JAMA 1986;255:2905-2989, 2. Lindner KH, Ahnefeld FW, SchuermannW, Bowdler IM. Epinephrineand norepinephrinein cardiopulmonary resuscitation.Effects on myocardial oxygen delivery and consumption.Chest 1990;97:1458-1462. 3. RobinsonLA, Brown CG, JenkinsJ, Van Ligten PF, Werman HA, Asthon J, Hamlin RL. The effect of norepinephrineversusepinephrineon myocardial hemodynamicsduring CPR. Ann Emerg Med 1989;18:336-340. 4. Brown CG, Werman HA. Adrenergic agonistsduring cardiopulmonary resuscitation Resuscitation 1990;19:1-16. 5. Smetana J, Racenberg E, Juna S, Markalous P. Resuscitationof the heart, experimental study and clinical experience.Rev Czech Med 1961;7:65-86. 6. Lindner KH, Ahnefeld FW. Comparisonof epinephrineand norepinephrinein the treatment of asphyxial or fibrillatory cardiac arrest in a porcine model. Ciit Care Med 1989;17:437-441.
Balloon Pulmonary
Valve Dilation in
Shakeel A. Qureshi, MB, MRCP, Eric RoSenthaI, MD, Michael Tynan, MD, Rui Anjos, MD, and Edward J. Baker, MD n patients with pulmonary atresia (with or without a ventricular septal defect), a series of operations are Irequired to achievecomplete repair. Theseoften include
Transcatheter laser-assisted pulmonic valve dilation was attempted for pulmonic valve atresia in 5 children aged between 5 dhys and 2 years (Table I). All had an initial systemicto pulmonary artery shunt, followed by pulmonic value atresia, with confluent central pulmoa pulmonary valvototiy or a patch or a conduit to estab- nary arteries: 2 had an associated ventricular septal delish right ventricle to pulmonary artery continuity, and by fect (patients 1 and 2) and 3 had an intact ventricular closure of the shunt and correction of any other defects. septum (patients 3 to 5). Inpatient 1, the centralpulmoWith the advent of newer interventional techniques,a nary arteries were also supplied by major aortopulmo-
number of congenital anomalies can be treated without surgery. Until now, pulmonic valve atresia was considered to lie beyond the scopeof such interventional transcatheter treatment, becauseof the inability to perforate the atretic valve safely. We report our initial experience of transcatheter laser-assistedpulmonic valve dilation in 5 children with pulmonic valve atresia. From the Department of Paediatric Cardiology, Guy’s Hospital, London SE1 9RT, United Kingdom. Manuscript received July 9, 1990; revised manuscript received October 19, 1990, and accepted October 20.
428
THE AMERICAN
JOURNAL
OF CARDIOLOGY
VOLUME
67
TABLE Pt. No.
I Clinical Data
Age
Weight (kg) & Sex
1
2 W)
9.1/M
2 3 4 5
2 (wk) 3 (day) 10 (wk) 40 (wk)
3.3/M 2.1/F 3.2/M 6.7/M
Diagnosis
Prior Surgery
Laser Route
Balloon Size (mm)
PVA.VSD PVA, VSD PVA, PDA PVA, PDA PVA
RBTs LBTs 0 0 LBTs
RV BTs RV RV BTs
35.7 5.7 3,5 3.v.7
LBTs = left &lock-Taussig shunt; PDA = patent ductus arteriosus; PVA = pulmonic valve atresla; RBTs = right Blalock-Tausslg shunt: RV = right ventricle: VSD = ventrlcular Sept.4 defect.
nary collateral arteries. A modified right Blalock-Taussig shunt with a 6-mm graft had been performed when patient 1 was aged 17 months. Patient 2 underwent a modified left Blalock-Taussigshunt with a 5-mm graft. In patients 3 and 4, the right ventricle was hypoplastic and both patients were dependent on the ductus arteriosus. Patient 5 also had a hypoplastic right ventricle and had a modified left Blalock-Taussig shunt with a 5-mm graft when he was 2 days old. When he was 10 months old, he developed increasing cyanosis, hepatomegaly and ascites because of a restrictive foramen ovale that resulted in a dilated right atrium and a moderatepericardial effusion. Cardiac catheterization was performed percutaneously by the femoral venous and arterial routes under general anesthesia in all patients, Usually a 5 or 6Fr multipurpose catheter was inserted through the venous sheath and a 5Fr multipurpose catheter through the arterial sheath. Angiography was performed in the right ventricular body or infundibulum, in the anteroposterior and lateral projections through the venous catheter. The arterial catheter was positioned in the main pulmonary artery through the Blalock-Taussig shunts in 3 patients and through the ductus arteriosus in 2. Angiography was performed in the pulmonary artery in the same projections. The pulmonary valve ring diameter was measured angiographically. In each patient, the venous and arterial catheters werepositioned close to the valve: 1 was used to pass the laser guidewire and the other was used as a landmark. The laser wire consisted of a 0.018-inch TeflonTM-coated guidewire, containing a 116qm optical Jiber and terminating in a 0.5-mm metal tip. The optical fiber was interfaced with a Nd-YAG laser generator (Cardiolase 4000, Trimedyne Inc., Santa Ana, California). In 3 patients (nos. 1, 3 and 4), the laser wire was introduced anterogradely and in 2 (nos. 2 and 5) retrogradely. The laser wire was passed a few millimeters beyond the catheter tip until it was in contact with the valve. The laser energy was delivered continuously at 3.5 Was the wire was advanced across the valve. Once the
laser wire was across the valve, a predilating catheter was passed over it, and this was followed by serial dilation of the valve using appropriately sized balloons far the pulmonary valve anulus (Table Z). Figures 1 and 2 show some of the details inpatients 3 and 5, respectively. In patient 4, the laser wire did not cross the valve and entered the pericardial cavity. No further attempts were made to cross the valve. Successful laser-assisted pulmonic valve dilation was accomplished in 4 patients (nos. 1, 2, 3 and 5) in whom the laser wire crossed the valve after delivery of energy for 3 to 5 seconds. The duration of the procedure was 3.5 to 5 hours. There was an increase in pulmonary artery pressure or a decrease in right ventricular pressure, with little change in systemic arterial pressure (Table ZZ). Afterward, patients I,2 and 5 were ventilated in the intensive care unit for 1 to 3 days before being returned to the ward. Patient 1 was discharged aftef 2 days, patient 2 after 10 days and patient 5 after 2 weeks. Inpatient 3, shortly after the laser wire was snared in the descending aorta, cardiac tamponade developed, which responded to percutaneous needle pericardiocentesis. After hemodynamic stability had returned, dilation with balloon catheters was achieved uneventfully. Two days later, the arterial duct had become smaller, despite continuation of prostaglandin infusion, and balloon dilation of the duct was therefore performed with a 3.5-mm balloon catheter. Patient 3 was extubated 15 days later. In patient 4; who had coexistent infundibular atresia, the laser wire passed into the pericardium from the infundibulum and caused immediate cardiac tamponade, which responded to needle aspiration. After hemodynamic stability was achieved, this patient underwent a systemic to pulmonary artery shunt operation, but died on the operating table. During a short 2- to 6-month follow-up of the 4 successful patients, the Doppler-estimated pressure drop across the right ventricular outflow ranged between 50 and 70 mm Hg, and there was evidence of pulmonary regurgitation in all patients. In patient 5, the pericardial
FIGURE 1. RiiM ventricular angiogram in the left lateral pro&tion showing pulmonic Qalve atresia. Catheter positioned in the main pulmonary artery has been passed through the arterial duct (Ieft). In the middle panel, the laser wire has b&n advanced across the pulmonary valve through the right ventricular catheter. Alter balloon dilation, right ventricular angiogram (right) shotis anterograde ttow across the pidmonary valve.
THE AMERICAN JOURNAL OF CARDIOLOGY FEBRUARY 15, 1991
429
FIGURE 2. Right ventricular angiogram (left) and angbgram in the main pulmonary artery (middle) detins the landmarks. laser-assisted pulmonary valve dilation, right ventricular angiogram (right) shows forward flow into the pulmonary artery.
effusion and ascites resolved. Transcutaneous oxygen saturations in the 4patients rangedfrom 70 to 87% and, in patient 3, the ductus arteriosus had closed. The first cardiac laser application was for an intraoperative pulmonary valvotomy in 1974.l Since then, several investigators have evaluatedthe technique experimentally,2,3but not clinically in children. In adults, bare fiber laser and “hot tip” laser thermal probeshavebeenusedto recanalizeperipheral artery occlusionswith variable success.4,5 In patients with pulmonary atresia and an intact ventricular septum,the hospital mortality for palliative operations (shunt with or without valvotomy) is approximately 1O%.6Some patients may require further palliative operations, either during the sameadmissionor over the next few years. Tbe subsequentdefinitive repair may have a hospital mortality rate of 25 to 50%.6In patients with pulmonary atresia associatedwith a ventricular septal defect, major aortopulmonary collateral arteries and confluent central pulmonary arteries, a staged surgical approach is frequently required in order to achieve a complete repair. The lo-year survival rate in the series reported by Kirklin et al7 was 69% in this group of patients. TABLE II Pressures (mm Hg) Before and After Pulmonic Valve Dilation
Pt. No. 1 2 3 4 5
Right Ventricle(s)
Pulmonary Artery (s/d)
Aorta (s/d)
Pre
Post
Pre
Post
Pre
Post
105
110 100 85 * 90
17/12 21/17 60/25 22/7
36/16 45/15 60/25 * 26/20
106/43 loo/55 go/27 110/40 96/34
115/45 96/50 85/25 * go/40
120 135 115 190
15/11
* Unsuccessful valve dilation. d = end diastok; s = peak systole.
430
THE AMERICAN JOURNAL OF CARDIOLOGY VOLUME 67
After
In this small preliminary series,our initial objective was to determine whether laser-assistedvalve dilation could establish anterograde flow acrossthe atretic pulmanic valves. In the long term, we need to establish whether the right ventricle and pulmonary artery will increasein size. Someof our initial patients had already undergonepalliative shunts,and their outflow tract anatomy was consideredsuitable for the future creation of surgical right ventricular to pulmonary artery continuity. In our first 2 patients, having established anterograde flow across the pulmonary valve, we hoped to achieve closureof the ventricular septaldefectwithout an interim operation on the right ventricular outflow tract. Thus, we wereencouragedto attempt laser-assistedpulmonic valve dilation and dilation of the ductus arteriosus in order to avoid any palliative surgery in patients with pulmonary atresia and an intact ventricular septum. Patient 3 has thus far avoidedany form of palliative surgery and we are monitoring her right ventricular function. Although patient 5 had a surgical shunt establishedin the neonatal period, this patient may likewise not needfurther operations, as the shunt could be occludednonsurgically when indicated. In retrospect,we feel that patient 4 wasunsuitable for laser-assistedpulmonic valve dilation, becauseof the combination of infundibular and pulmonic valve atresia. This reducedthe safety margin when the laser guidewire was directed toward the pulmonary artery. We believethat our first objective of establishinganterograde flow across the pulmonic valve has been achievedand that laser-assistedvalve dilation is feasible in neonates,infants and children with pulmonic valve atresia. However, it should be avoidedin thosewith associated infundibular atresia. Further follow-up is needed to determine whether our long-term objectives can be achieved by this approach. Acknowledgment: We thank Trimedyne Inc. for providing us with the laser guidewires, Paul V. L. Curry, MD, of Guy’s Hospital, and David C. Cumberland, MD, of Northern General Hospital, Sheffield, United King-
dom, for their helpful advice, and Deo Persaud, Cordis, United Kingdom, for providing technical assistance.
1. Arapov AD, Vishnerskii AA Jr, Abdullaev FZ, Korchagin VA, Mirtskhulava KA, Sorgin ME. A preliminary report on laser application in cardiosurgery. Eksp Khir Anesteziol 1914;4:10-12. 2. Macruz R, Martins JRM, Tupinnamba HS, Lopes EA, Varbas H, Penna AF, Carvalho VB, Armelin E, Decourt LV. Possibilidades terapeuticas do raio laser em ateromas. Arq Bras Cardiol 1980;34:9-12. 3. Riemenschneider TA, Lee G, Ikeda RM, Bommer WJ, Stobbe D, Ogata C, Rebeck K, Reis RL, Mason DT. Laser irradiation of congenital heart disease:
potential for palliation and correction of intracardiac and intravascular defects. Am Heart J 1983;106:1389-1393. 4. Ginsburg R, Wexler L, Mitchell RS, Proffit D. Percutaneous transluminal laser angioplasty for treatment of peripheral vascular disease. Clinical experience with 16 patients. Radiology 1985;156:619-624. 8. Sanborn TA, Cumberland DC, Welsh CL, Greenfield AJ, Guben JK. Percutaneous laser thermal angioplasty: initial results and 1 year follow-up in 129 femoropopliteal lesions. Radiology 1988;168:121-125. 6. Kirklin JW, Barratt-Boyes BG. Cardiac surgery. New York: John Wiley, 1986:821-856. 7. Kirklin JW, Blackstone EH, Shimaznki Y, Maehara T, Pacific0 AD, Kirklin JK, Bargeron LM Jr. Survival, functional status, and reoperations after repair of tetralogy of Fallot with pulmonary atresia. J The-m Cardiovasc Surg 1988; 96:102-116.
Atherectomy of Right Coronary Ostial Stenoses: Initial and LongTerm Results, Technical Features and Histologic Findings Jeffrey J. Popma, MD, Ronald J. L. Dick, MBBS, Christian C. Haudenschild, MD, Eric J. Topol, MD, and Stephen G. Ellis, MD oronary angioplasty of lesions involving the right coronary ostium has been limited by suboptimal early successand by high rates of both acute complications and late restenosis.’In nonostial stenoses,directional coronary atherectomy appearsto result in larger residual coronary dimensionsthan doescoronary angioplasty2 and may provide a potentially improved long-term outcome.To determine the immediate and long-term angiographic results of directional atherectomy in patients with right ostial stenoses,we attempted this procedurein 7 consecutive patients with coronary stenoseswithin 3 mm of the right coronary ostium. c
isfactory angiographic result was obtained. Patients were monitoredfor evidence of abrupt closure and intravascular sheaths were removed within 12 hours. Successful atherectomy was defined as a 50% in diameter within 3 mm of the orifice of the right coronary artery.’ After informed consent and pretreatment with aspirin, a calcium antagonist and 10,000 to 15,000 U of intravenous heparin, a 9.5 to 1I Fr guiding catheter (Devicesfor Vascular Intervention, Inc., Redwood City, California) was advanced to the right coronary ostium. A O.Oll-inch coronary guidewire was positioned across the coronary stenosis andpredilation performed with an undersized standard angioplasty balloon (Figure 1). A 5 to 7Fr atherectomy device (Devices for Vascular Intervention, Inc.) was then positioned across the right coronary ostium and the guiding catheter was withdrawn into the ascending aorta. Coronary atherectomy was then performed by the method previously described3 until a satFrom the Department of Internal Medicine, Division of Cardiology BlF245, University of Michigan Medical Center, 1500 E. Medical Center Drive, Ann Arbor, Michigan 48109-0022, and the Cardiovascular Research Laboratory, Mallory Institute of Pathology, Boston College, Boston, Massachusetts. Manuscript received September 17, 1990; revised manuscript received and accepted October 25, 1990.
FIGURE 1. Top left, left anterior oblique projection of a right coronary ostial lesion. Note streaming artifact from inability to fill the distal vessel adequately. Top right, after predilation with an undersized balloon catheter, the atherectomy device is positioned in the coronary ostium and the guiding catheter is withdrawn slightly (lower leff). The coronary ostiim is widely patent immediately after coronary atherectomy (rower rightJ.
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