TO THE EDITOR
To the Editor: We read with interest the report by Bashour et a1.l in a recent issue of the JOURNAL. We reported an identical case in 1985,s Our article cited four cases with bradyarrhythmias and tachyarrhythmias complicating angina, in which angiography demonstrated stenosis of a single major coronary artery. In the patient with prolonged angina, sinus arrest, and proximal right coronary stenosis, angioplasty of the diseased vessel resulted in the return of sinus rhythm. Repeat coronary angiography 4 months later showed that the artery remained patent, and the patient remained in sinus rhythm without further syncope. Until the end of 1987, when I left that cardiac center, there had been no recurrences of sinus node dysfunction or syncope. Coronary artery disease accounts for less than 20 “1 s of cases of sick sinus syndrome. The remainder are associated with degeneration, fibrosis, or amyloid infiltration of the sinus node. Nevertheless, in view of the known infective complications of permanent pacemaker implantation, we believe a possible ischemic cause should be sought. We are of the opinion that since the risk of restenosis after coronary angioplasty is greatest in the first 6 months4 close follow-up during this period rather than prophylactic implantation of a permanent pacemaker should be considered. Adeniyi 0. Molajo, MD Leigh Infirmary The Avenue Leigh Lancashire WN7 1HS England REFERENCES
Bashour TT, Chen F, Feeney J. Ischemic sinus node hibernation: resolution following angioplasty. AM HEART J 1991: 122:1156-8. Molajo AO, Summers GD, Bennett DH. Effect of percutaneous transluminal coronary angioplasty on arrhythmias complicating angina. Br Heart J 1985;54:375-7. Shaw DB. Sino-atria1 dysfunction-sick sinus syndrome. In: Sleight P, Jones JV, eds. Scientific foundations in cardiology. London: Heinemann, 1983:363-4. Nobuyoshi M, Kimura T, Nosaka M, Moika S, Ueno K, Yokoi H. Hamasaki N. Horiuchi H. Oshishi H. Restenosis after successful percutaneous transluminal coronary angioplasty: serial angiographic follow-up of 229 patients. J Am Co11 Cardiol 1988;12:616-23.
REPLY To the Editor: We appreciate the comments of Dr. Molajo regarding our report on ischemic sinus node dysfunction. As he states, this represents about one fifth of all cases of sick sinus syndrome. We have also debated whether to implant a permanent pacemaker after successful angioplasty of proximal total occlusion of the right coronary artery. Considering the total “shut ofI” phenomenon encountered in our patient with no escape rhythm in evidence, and the expected high risk of restenosis after total occlusion (approximately 50%), we decided in favor of pacemaker implantation rather than risking the consequences, which might include sudden
death outside the hospital. In less severe cases where prolonged standstill is not found, careful close follow-up for at least 6 months may be considered. Tali T. Bashour, MD Western Heart Institute St. Mary’s Hospital and Medical Center -150 Stanyan St. San E’rancisco, CA 94 1 I7 4/S/41813
BALLOON VALVOTOMY OF MITRAL BIOPROSTHETIC STENOSIS To the Editor: We read with interest the report by Spellberg et a1.i in the December 1991 issue of the JOURNAL. The authors stated that theirs was the first report of successful balloon valvuloplasty in a mitral calf pericardium bioprosthesis. We point out that Babic et al.” also reported a case of successful valvuloplasty in a similar tissue valve with the added use of a protective device to prevent thromboembolism. It has been proved by in vitro studies”,* of excised bioprosthetic valves that the primary mechanism responsible for increase in valve area is leaflet tearing and fracturing rather than commissural splitting. On removal of deflated balloons and emboli-protecting devices after the procedure, small clots and calcium debris were detected, suggesting a risk of thromboembolism, although the actual risk is not known.2 Until now there has been no large study or good follow-up of bioprosthetic stenosis treated with balloon valvuloplasty to assess the risks and benefits of this procedure. Such a study is needed to define the role of balloon valvuloplasty. S. Chandra bose Reddy, MD Gala1 M. Ziady, MD Division of Cardiology Presbyterian University Hospital DeSoto at O’Hara St. Pittsburgh, PA 1521.3 REFERENCES
Spellberg RD, Mayeda GS, Flores JH. Balloon valvuloplasty AM HEART .J of a stenosed mitral bioprosthesis. 1991;122:1785-7. Babic UV, Girujicic S, Vucinic M. Balloon valvuloplasty of mitral bioprosthesis. Int J Cardiol 1991;30:230-2. Riberio PA, al Zaibag M, Sawyer W. The valve and extent of valve area increase by balloon dilatation of the stenosed bioprosthesis: in vitro studies. Rev Port Cardiol 1989;8:515-8. Velasco LM, Vasquez RV, Valdez JL, et al. Valvuloplasty with balloon catheter in biologic prosthesis. Reality or illusion. Arch Inst Cardiol Mex 1989;59:69-71. 4/8/41814
REPLY To the Editor: We thank Drs. Chandra bose Reddy and Ziady for bringing our attention the recent report of successful balloon valvuloplasty