Chronotropic incompetence: a case report.

Chronotropic incompetence is generally defined as an inadequate heart rate response to exercise, but manifestations can vary. The incidence depends on underlying cardiac pathology and, to a lesser degree, on the cut-off value of the predicted heart rate during exercise. Different pathologies induce chronotropic incompetence. Its presence indicates an adverse outcome and is strongly correlated with coronary artery disease. Treatment consists of rate-responsive pacemakers; dual-sensor, adaptive pacemakers are superior to single-sensor, rate-augmenting pacemakers. This case report illustrates the negative effect of chronotropic incompetence on daily activities and its amelioration by implantation of a rate-responsive pacemaker. (c)2001 by CHF, Inc.

Coronary aneurysm five months after intracoronary beta-irradiation.

Intracoronary beta-irradiation is believed to be useful in preventing restenosis after coronary angioplasty or as adjunct therapy of an in-stent restenosis. Intracoronary aneurysms after gamma-irradiation were reported by Condado et al. in 1995, especially after doses higher than 25 Gy and without a centering device. In repeated small trials using intracoronary beta-irradiation no aneurysms were reported at 6 months follow-up. We report the development of a coronary aneurysm at 5 months after intracoronary beta-irradiation and stenting. Intracoronary brachytherapy is a new promising technique although one should be cautious about its possible unknown long-term complications.

Six months clinical, angiographic, and IVUS follow-up after PTFE graft stent implantation in native coronary arteries.

INTRODUCTION: Restenosis remains a problem even after stent implantation. An important breakthrough could be the use of graft stents, functioning as a mechanical barrier between the blood flow and the vessel wall, and possibly inducing less restenosis by more limited hyperplasia and minimal transgraft tissue penetration. OBJECTIVE: To assess the acute and 6 months clinical, angiographic and IVUS results of a new balloon expandable coronary polytetrafluoroethylene (PTFE) graft stent (Jomed). METHOD: Ten patients with a short (< or = 15 mm length) de novo proximal stenosis in a large (> or = 3 mm diameter) coronary artery were treated by elective implantation of a graft stent (19 mm stent, 15 mm graft). Clinical assessment, quantitative coronary angiography (QCA) and intracoronary ultrasound (IVUS) were performed before, immediately after and 6 months after implantation. A stress test was also done at 6 months. RESULTS: The coronary arteries treated were: RCA in 7 patients, LCX in 2 patients, LAD in 1 patient. Mean balloon size was 3.7 mm diameter, and mean inflation pressure was 18 atm (min. 12, max. 23). Additional stenting was needed in 3 patients. Two patients showed a minimal rise in CK (< 250 IU/l) and 1 patient needed a transfusion. No patient experienced a (sub)acute nor late thrombosis. As shown in the table, no restenosis was seen in the body of the graft stent. In 2 patients a restenosis was detected in the proximal and/or distal parts of the stent which are not covered by the graft. In 1 patient a restenosis was found outside the stent. All patients remained asymptomatic with a negative stress test at 6 months follow-up (FU). [table in text] CONCLUSIONS: A graft stent could indeed reduce the restenosis rate after stenting, in the part of the stent covered by the graft, but the uncovered distal and proximal parts are the weak points in this type of stent. For this reason, technical ameliorations in the construction of this graft stent are needed, e.g. a complete coverage of the stent by the PTFE graft and less rigidity of the stent causing reduced vessel trauma at the edges of the stent during implantation.

Prinzmetal's variant angina: three case reports and a review of the literature.

Prinzmetal's variant angina is a rare entity. When angina-like symptoms occur at rest, mostly at a specific hour in the early morning, together with transient ST segment elevations and angiographically normal arteries, provocative tests with ergonovine or acetylcholine should be performed. Endothelial dysfunction, a strong thrombotic tendency, an increased platelet aggregation together with changes in autonomic tone can trigger coronary vasospasms. Once treated with calcium antagonists and nitrates the prognosis is excellent and severe complications such as arrhythmias, myocardial infarction or sudden death are extremely rare. Coronary stenting can be useful for refractory coronary spasm, CABG can be used for important coronary atherosclerosis. This review is illustrated with three typical presentations of variant angina: a myocardial infarction without significant organic coronary atherosclerosis, an ergonovine-induced coronary spasm with a non-significant coronary lesion and a multivessel spasm complicated by ventricular arrhythmia. All these three patients became asymptomatic after a treatment with calcium antagonists and nitrates.