clinical cardiology: original article
Percutaneous coronary intervention delays pacemaker implantation in coronary artery disease patients with established bradyarrhythmias Lihua Zhong MD*, Yanhui Gao MD*, Hongyuan Xia MD, Xueqi Li MD, Shipeng Wei MD L Zhong, Y Gao, h Xia, X Li, s Wei. Percutaneous coronary intervention delays pacemaker implantation in coronary artery disease patients with established bradyarrhythmias. exp Clin Cardiol 2013;18(1):17-21. BaCkGround: Pacemakers have long been used to assist the heart under pathological conditions, and they are the first choice in the treatment of systematic bradyarrhythmias. However, the effect of percutaneous coronary intervention (PCI) in patients with coronary artery disease as well as bradyarrhythmias remains unknown. Methods: In the present study, 42 patients with chest pain and/or abnormal stress test results were surveyed. Before coronary angiography, patients underwent complete examination, including a 24 h dynamic electrocardiogram, which was used to diagnose bradyarrhythmias that were not suitable for pacemaker implantation due to a lack of arrhythmia-related symptoms. All patients underwent PCI but did not undergo pacemaker implantation. Fortyone patients with chest pain and/or abnormal stress test results, as well as symptom-free bradyarrhythmias, were selected as the control group. All of the patients in the control group were committed to treatments without PCI.
B
radyarrhythmia is a common disorder encountered in clinical practice. It can be related to cardiac diseases, of which coronary artery disease (CAD) is one of the most common, or to other systemic abnormalities (1-4). Furthermore, bradyarrhythmia is often observed in patients with acute myocardial infarction (5,6) or coronary artery bypass graft, and in patients experiencing exercise-induced relative ischemia (7-9). This phenomenon can be prevented through the timely restoration of blood flow in the coronary arteries; therefore, few patients with acute myocardial infarction need pacemakers (10). Even in situations where the occlusion of certain coronary arteries is necessary for treatment, the accompanying bradyarrhythmias remain transient and pacemaker implantation is rarely necessary (11). The relationship between bradyarrhythmias and chronic ischemic heart disease has been studied by several groups (12-15). Bradyarrhythmias are not only the result of chronic heart disease, but also have relationships with specific coronary artery lesion types not observed in CAD patients without bradyarrhythmias (12-15). However, unlike acute ischemia of the heart, in chronic cardiac ischemia, revascularization may not help in correcting bradyarrhythmias (16). Because damage to the conduction system is irreversible, in addition to stents, pacemaker implantation has been the traditional treatment for bradyarrhythmias. Although the use of stents in these patients is believed to be necessary, the effect of revascularization on the progress of bradyarrhythmias is currently unknown. According to guidelines for pacemaker implantation, the use of pacemakers in patients who exhibit arrhythmia-related symptoms is emphasized (17). The indication for pacemaker use in patients with arrhythmia-related symptoms is broader than in patients without symptoms, especially those with bradyarrhythmias. Some may, therefore, question the necessity for symptom-free patients to undergo pacemaker implantation and whether there are other ways to help these patients. Given that CAD is related to bradyarrhythmias, we hypothesized that revascularization would delay the need for pacemakers in bradyarrhythmias patients. In the present study, we surveyed
resuLts: During a mean (±SD) of 3.3±0.5 years of follow-up (range 2.5 to 4.5 years), 24 of 42 patients who received PCI underwent pacemaker implantation for arrhythmia-related symptoms, eight were shown by Holter monitoring to have worsened but still exhibited no symptoms, and the remainder did not show any changes according to the examinations performed. In the control group, 31 patients underwent pacemaker implantation for arrhythmia-related symptoms, eight were shown by Holter monitoring to have worsened but still exhibited no symptoms, and two did not show any changes according to the examinations performed. Nevertheless, the rates of pacemaker implantation each year (from the first to the third year) between the two groups were 7.1% versus 39.0% (P=0.001); 33.3% versus 63.4% (P=0.006); and 57.1% versus 75.6%, (P=0.075), respectively. ConCLusions: The present study found that PCI delayed the demand for pacemaker implantation among coronary artery disease patients. key Words: Pacemaker; Percutaneous coronary intervention; Sinus node diseases
more than 10,000 patients who had received coronary angiography and selected for follow-up those patients diagnosed with CAD as well as bradyarrhythmias to prove our hypothesis.
Methods
study population More than 10,000 medical records of consecutive symptomatic patients with chest pain and/or abnormal stress test results who were admitted to The Fourth Clinical Hospital of Harbin Medical University (Harbin, China) and underwent coronary angiography between 2003 and 2007 were reviewed. Of the 1518 patients receiving percutaneous coronary intervention (PCI), 42 patients who were diagnosed with bradyarrhythmia, without any arrhythmia-related symptoms, using a 24 h dynamic electrocardiogram test were enrolled. Of 846 patients who had symptomfree bradyarrhythmias, 41 were chosen to represent the control group. Although these patients could have also received PCI, they were committed to alternative treatments for the following reasons: eight patients refused PCI for personal reasons (three refused PCI for psychological reasons and the remaining five refused PCI for economic reasons); 12 patients were found to have severe CAD and were indicated for coronary artery bypass graft (CABG) surgery, but all of them refused; 13 patients had borderline lesions and intravascular ultrasound scans showed that the lesions were stable; therefore, the doctors chose treatments without PCI; and eight patients had stable angina and were capable of performing daily activities; therefore, considering their ages, it was decided they did not require PCI. According to the American College of Cardiology (ACC) and the American Heart Association (AHA) guideline for implantation of cardiac pacemakers and arrhythmia devices, correlation of symptoms with arrhythmias resulting from sinus node dysfunction is essential in deciding whether a permanent pacemaker is indicated. In other words, asymptomatic patients do not qualify as pacemaker implantation candidates (17). None of the patients in the control group underwent pacemaker implantation and all the patients underwent a mean (± SE) of 3.3±0.5 years (2.5 to 4.5 years) of follow-up.
*Both authors contributed equally to this work Department of Cardiology, The Fourth Clinical Hospital of Harbin Medical University, Harbin, China Correspondence: Dr Shipeng Wei, Department of Cardiology, The Fourth Clinical Hospital of Harbin Medical University, 37 Yiyuan Street, Nangang District, Harbin 150001, China. Telephone and fax 86-45182576977, e-mail [email protected]
Exp Clin Cardiol Vol 18 No 1 2013
©2013 Pulsus Group Inc. All rights reserved
17
Zhong et al
Physical examination Blood pressure, including systolic and diastolic pressure, and heart rate were recorded on admission. The patient’s history with respect to other diseases, such as hypertension and diabetes, was also recorded. Coronary angiography Coronary angiography was performed using the standard Judkin technique in all patients who provided written consent, as described previously (15). Stenosis of >50% in one of the three major coronary arteries, including the left anterior descending artery (LAD), left circumflex artery (LCX) and right coronary artery (RCA), or their firstorder branches was considered to be severe CAD, while 10% to 50% stenosis was considered to be mild CAD and 70% in any one of the three major coronary arteries including the LAD, LCX and RCA, or their first-order branches indicated the requirement for PCI. 24 h dynamic electrocardiogram Bradyarrhythmias were diagnosed in patients either by 24 h dynamic electrocardiogram before PCI or after PCI while in hospital. Patients with positive results were subsequently followed-up. Patients underwent a 24 h dynamic electrocardiogram at least once every six months until pacemaker implantation was performed. Left ventricular ejection fraction The methods used for determination of the left ventricular ejection fraction were described previously (15). The left ventricular ejection fraction of the patients was confirmed by echocardiographic assessment. Classification of pathological coronary anatomy supplying the conduction system The location of narrowings in the LAD and RCA, the arteries that supply the conduction system, was documented accurately and classified according to Mosseri et al (12): • Type I. Anatomy not compromising blood supply to the conduction system, namely, either the absence of significant narrowing in the LAD, RCA, LCX, posterolateral branch or posterior descending artery, or the presence of mid-distal LAD lesions beyond the septal branches. • Type II. Pathological coronary anatomy involving septal branches emerging from the LAD (and without significant lesions in the RCA). • Type III. Pathological coronary anatomy compromising blood supply to the sinoatrial or atrioventricular nodes but not compromising blood flow to the septal branches. This subset includes patients with distal LAD lesions after the septal branches. • Type IV. Combination of Type II and Type III pathological coronary anatomy that compromises blood supply both to the septal branches and the sinoatrial or atrioventricular nodes. Laboratory tests After an overnight fast (≥12 h), blood samples were drawn from all patients in the morning hours before coronary angiography (CAG) following 15 min of bed rest in a quiet room. Briefly, blood samples were collected and centrifuged, and the serum was extracted for use. All kits were purchased from Roche (Germany). The biochemical examination was performed using an automated analytics system (Modular Analytics P, Roche, Germany). Levels of total cholesterol, trigylcerides, low-density lipoprotein and high-density lipoprotein were measured and recorded for analysis. statistical analysis SPSS version 17.0 (IBM Corporation, USA) was used to analyze the data. Results were reported as group means ± SE. A one-way ANOVA was used to determine differences among the group means; P
Percutaneous coronary intervention delays pacemaker implantation in coronary artery disease patients with established bradyarrhythmias Lihua Zhong MD*, Yanhui Gao MD*, Hongyuan Xia MD, Xueqi Li MD, Shipeng Wei MD L Zhong, Y Gao, h Xia, X Li, s Wei. Percutaneous coronary intervention delays pacemaker implantation in coronary artery disease patients with established bradyarrhythmias. exp Clin Cardiol 2013;18(1):17-21. BaCkGround: Pacemakers have long been used to assist the heart under pathological conditions, and they are the first choice in the treatment of systematic bradyarrhythmias. However, the effect of percutaneous coronary intervention (PCI) in patients with coronary artery disease as well as bradyarrhythmias remains unknown. Methods: In the present study, 42 patients with chest pain and/or abnormal stress test results were surveyed. Before coronary angiography, patients underwent complete examination, including a 24 h dynamic electrocardiogram, which was used to diagnose bradyarrhythmias that were not suitable for pacemaker implantation due to a lack of arrhythmia-related symptoms. All patients underwent PCI but did not undergo pacemaker implantation. Fortyone patients with chest pain and/or abnormal stress test results, as well as symptom-free bradyarrhythmias, were selected as the control group. All of the patients in the control group were committed to treatments without PCI.
B
radyarrhythmia is a common disorder encountered in clinical practice. It can be related to cardiac diseases, of which coronary artery disease (CAD) is one of the most common, or to other systemic abnormalities (1-4). Furthermore, bradyarrhythmia is often observed in patients with acute myocardial infarction (5,6) or coronary artery bypass graft, and in patients experiencing exercise-induced relative ischemia (7-9). This phenomenon can be prevented through the timely restoration of blood flow in the coronary arteries; therefore, few patients with acute myocardial infarction need pacemakers (10). Even in situations where the occlusion of certain coronary arteries is necessary for treatment, the accompanying bradyarrhythmias remain transient and pacemaker implantation is rarely necessary (11). The relationship between bradyarrhythmias and chronic ischemic heart disease has been studied by several groups (12-15). Bradyarrhythmias are not only the result of chronic heart disease, but also have relationships with specific coronary artery lesion types not observed in CAD patients without bradyarrhythmias (12-15). However, unlike acute ischemia of the heart, in chronic cardiac ischemia, revascularization may not help in correcting bradyarrhythmias (16). Because damage to the conduction system is irreversible, in addition to stents, pacemaker implantation has been the traditional treatment for bradyarrhythmias. Although the use of stents in these patients is believed to be necessary, the effect of revascularization on the progress of bradyarrhythmias is currently unknown. According to guidelines for pacemaker implantation, the use of pacemakers in patients who exhibit arrhythmia-related symptoms is emphasized (17). The indication for pacemaker use in patients with arrhythmia-related symptoms is broader than in patients without symptoms, especially those with bradyarrhythmias. Some may, therefore, question the necessity for symptom-free patients to undergo pacemaker implantation and whether there are other ways to help these patients. Given that CAD is related to bradyarrhythmias, we hypothesized that revascularization would delay the need for pacemakers in bradyarrhythmias patients. In the present study, we surveyed
resuLts: During a mean (±SD) of 3.3±0.5 years of follow-up (range 2.5 to 4.5 years), 24 of 42 patients who received PCI underwent pacemaker implantation for arrhythmia-related symptoms, eight were shown by Holter monitoring to have worsened but still exhibited no symptoms, and the remainder did not show any changes according to the examinations performed. In the control group, 31 patients underwent pacemaker implantation for arrhythmia-related symptoms, eight were shown by Holter monitoring to have worsened but still exhibited no symptoms, and two did not show any changes according to the examinations performed. Nevertheless, the rates of pacemaker implantation each year (from the first to the third year) between the two groups were 7.1% versus 39.0% (P=0.001); 33.3% versus 63.4% (P=0.006); and 57.1% versus 75.6%, (P=0.075), respectively. ConCLusions: The present study found that PCI delayed the demand for pacemaker implantation among coronary artery disease patients. key Words: Pacemaker; Percutaneous coronary intervention; Sinus node diseases
more than 10,000 patients who had received coronary angiography and selected for follow-up those patients diagnosed with CAD as well as bradyarrhythmias to prove our hypothesis.
Methods
study population More than 10,000 medical records of consecutive symptomatic patients with chest pain and/or abnormal stress test results who were admitted to The Fourth Clinical Hospital of Harbin Medical University (Harbin, China) and underwent coronary angiography between 2003 and 2007 were reviewed. Of the 1518 patients receiving percutaneous coronary intervention (PCI), 42 patients who were diagnosed with bradyarrhythmia, without any arrhythmia-related symptoms, using a 24 h dynamic electrocardiogram test were enrolled. Of 846 patients who had symptomfree bradyarrhythmias, 41 were chosen to represent the control group. Although these patients could have also received PCI, they were committed to alternative treatments for the following reasons: eight patients refused PCI for personal reasons (three refused PCI for psychological reasons and the remaining five refused PCI for economic reasons); 12 patients were found to have severe CAD and were indicated for coronary artery bypass graft (CABG) surgery, but all of them refused; 13 patients had borderline lesions and intravascular ultrasound scans showed that the lesions were stable; therefore, the doctors chose treatments without PCI; and eight patients had stable angina and were capable of performing daily activities; therefore, considering their ages, it was decided they did not require PCI. According to the American College of Cardiology (ACC) and the American Heart Association (AHA) guideline for implantation of cardiac pacemakers and arrhythmia devices, correlation of symptoms with arrhythmias resulting from sinus node dysfunction is essential in deciding whether a permanent pacemaker is indicated. In other words, asymptomatic patients do not qualify as pacemaker implantation candidates (17). None of the patients in the control group underwent pacemaker implantation and all the patients underwent a mean (± SE) of 3.3±0.5 years (2.5 to 4.5 years) of follow-up.
*Both authors contributed equally to this work Department of Cardiology, The Fourth Clinical Hospital of Harbin Medical University, Harbin, China Correspondence: Dr Shipeng Wei, Department of Cardiology, The Fourth Clinical Hospital of Harbin Medical University, 37 Yiyuan Street, Nangang District, Harbin 150001, China. Telephone and fax 86-45182576977, e-mail [email protected]
Exp Clin Cardiol Vol 18 No 1 2013
©2013 Pulsus Group Inc. All rights reserved
17
Zhong et al
Physical examination Blood pressure, including systolic and diastolic pressure, and heart rate were recorded on admission. The patient’s history with respect to other diseases, such as hypertension and diabetes, was also recorded. Coronary angiography Coronary angiography was performed using the standard Judkin technique in all patients who provided written consent, as described previously (15). Stenosis of >50% in one of the three major coronary arteries, including the left anterior descending artery (LAD), left circumflex artery (LCX) and right coronary artery (RCA), or their firstorder branches was considered to be severe CAD, while 10% to 50% stenosis was considered to be mild CAD and 70% in any one of the three major coronary arteries including the LAD, LCX and RCA, or their first-order branches indicated the requirement for PCI. 24 h dynamic electrocardiogram Bradyarrhythmias were diagnosed in patients either by 24 h dynamic electrocardiogram before PCI or after PCI while in hospital. Patients with positive results were subsequently followed-up. Patients underwent a 24 h dynamic electrocardiogram at least once every six months until pacemaker implantation was performed. Left ventricular ejection fraction The methods used for determination of the left ventricular ejection fraction were described previously (15). The left ventricular ejection fraction of the patients was confirmed by echocardiographic assessment. Classification of pathological coronary anatomy supplying the conduction system The location of narrowings in the LAD and RCA, the arteries that supply the conduction system, was documented accurately and classified according to Mosseri et al (12): • Type I. Anatomy not compromising blood supply to the conduction system, namely, either the absence of significant narrowing in the LAD, RCA, LCX, posterolateral branch or posterior descending artery, or the presence of mid-distal LAD lesions beyond the septal branches. • Type II. Pathological coronary anatomy involving septal branches emerging from the LAD (and without significant lesions in the RCA). • Type III. Pathological coronary anatomy compromising blood supply to the sinoatrial or atrioventricular nodes but not compromising blood flow to the septal branches. This subset includes patients with distal LAD lesions after the septal branches. • Type IV. Combination of Type II and Type III pathological coronary anatomy that compromises blood supply both to the septal branches and the sinoatrial or atrioventricular nodes. Laboratory tests After an overnight fast (≥12 h), blood samples were drawn from all patients in the morning hours before coronary angiography (CAG) following 15 min of bed rest in a quiet room. Briefly, blood samples were collected and centrifuged, and the serum was extracted for use. All kits were purchased from Roche (Germany). The biochemical examination was performed using an automated analytics system (Modular Analytics P, Roche, Germany). Levels of total cholesterol, trigylcerides, low-density lipoprotein and high-density lipoprotein were measured and recorded for analysis. statistical analysis SPSS version 17.0 (IBM Corporation, USA) was used to analyze the data. Results were reported as group means ± SE. A one-way ANOVA was used to determine differences among the group means; P
