Lewis Wexler

Prevention Conference V Beyond Secondary Prevention : Identifying the High-Risk Patient for Primary Prevention : Noninvasive Tests of Atherosclerotic Burden : Writing Group III

Writing Group I of Prevention Conference V considered the role of routine office-based measures for assessing global risk in asymptomatic persons. With the physician-directed office risk assessment as a foundation, further risk stratification may be valuable, especially when the risk estimate is neither clearly low risk nor high risk (intermediate risk). For the intermediate-risk patient, further testing might include ≥1 noninvasive measure of atherosclerotic burden. Pathology studies have documented that levels of traditional risk factors are associated with the extent and severity of atherosclerosis. However, at every level of risk factor exposure, there is substantial variation in the amount of atherosclerosis. This variation in disease is probably due to genetic susceptibility; combinations and interactions with other risk factors, including life habits; duration of exposure to the specific level of the risk factors; and such factors as biological and laboratory variability. Thus, subclinical disease measurements, representing the end result of risk exposures, may be useful for improving coronary heart disease (CHD) risk prediction. Noninvasive tests such as carotid artery duplex scanning, electron beam–computed tomography (EBCT), ultrasound-based endothelial function studies, ankle/brachial blood pressure ratios, and magnetic resonance imaging (MRI) techniques offer the potential for directly or indirectly measuring and monitoring atherosclerosis in asymptomatic persons. High-sensitivity testing for C-reactive protein (hs-CRP) may also represent a measure of atherosclerosis “burden” and may therefore be considered another potential marker of atherosclerosis disease risk. The Prevention Conference V participants considered the status of several measures of subclinical disease in CHD risk assessment. The discussion that follows is a summary of the data reviewed and discussed at Prevention Conference V. During the discussion groups at Prevention Conference V, the ankle-brachial blood pressure index (ABI) was considered as a means of predicting CHD events. The ABI is a simple, inexpensive diagnostic test for lower-extremity peripheral arterial disease (PAD). …

Isolated Single Coronary Artery: Diagnosis, Angiographic Classification, and Clinical Significance

Isolated single coronary artery is a rare congenital anomaly occuring in approximately 0.024% of the population. This entity can be diagnosed during life only by coronary angiography. Ten patients with isolated single coronary artery are reported. Based on angiographic analysis, a new classification is proposed, according to the site of origin and anatomical distribution of the branches. Typical angina did not occur with single coronary artery in the absence of coexisting coronary artery disease or aortic stenosis. No correlation was apparent between the type of anomalous patterns and the symptoms of angina.

Provocation of coronary spasm with ergonovine maleate: New test with results in 57 patients undergoing coronary arteriography☆

Ergonovine maleate (Ergotrate) was given to 57 patients undergoing coronary arteriography for investigation of angina occurring at rest or without provocation when routine study showed normal arteries or insufficient occlusive disease to explain their symptoms. This provocative test induced coronary arterial spasm in 13 patients, 10 of whom had definite Prinzmetals angina. The spasm was easily reversed with sublingually administered nitroglycerin. The spasm was occlusive or nearly occlusive in nine patients, and there was associated reproduction of the chest pain and S-T elevation similar to the spontaneous episodes. One patient with Prinzmetals angina had S-T depression rather than elevation in association with the chest pain. The other three patients without Prinzmetals angina had focal narrowing without coronary occlusion, reproduction of the chest pain or electrocardiographic changes. Of the 44 patients who did not demonstrate coronary spasm in response to ergonovine, 29 had normal coronary arteries and 15 had various degrees of atherosclerotic occlusive disease. We conclude that cautious administration of ergonovine maleate during coronary arteriography can be safely used to elicit coronary spasm in some patients who have insufficient fixed occlusive disease to explain their symptoms.

Coronary arterial narrowing in Takayasu's aortitis

A patient with Takayasus aortitis and angina pectoris due to severe narrowing of the right and left coronary arterial ostia is described. Takayasus arteritis produces a panaortitis, with thickening of the adventitia predominating, and an inflammatory cell infiltrate involving the adventitia, outer media and vasa vasorum. Narrowing of the coronary arteries in this disease is due to extension into these arteries of the processes of proliferation of the intima and contraction of the fibrotic media and adventitia that occur in the aorta. The distal coronary arteries usually do not manifest arteritis and are normal in caliber. Angina pectoris may be the first symptom of the disease if the coronary arteries are the initial site of severe arterial narrowing. The coronary arterial bypass graft operation is effective therapy for treating coronary arterial narrowing due to Takayasus arteritis.

Clinical and arteriographic features of Prinzmetal's variant angina: Documentation of etiologic factors

Coronary arteriography performed in 17 patients with Prinzmetals variant angina demonstrated high grade fixed obstructions in 9 patients (Group I) and insignificant or no fixed lesions in 8 patients (Group II). Group I consisted mostly of middle-aged or elderly men with S-T segment elevations in various sites; Group II included five younger women with S-T segment elevations in inferior electrocardiographic leads. In Group I patients, arteriography revealed a discrete high grade lesion located proximally in a major coronary artery in four patients and multivessel involvement in five patients. In Group II patients, spontaneous spasm was documented in three patients and spasm was pharmacologically provoked in two others during arteriography. The current study indicates that spasm is the responsible pathogenetic mechanism of myocardial ischemia in some patients with Prinzmetal angina and that this mechanism may be suspected from the clinical characteristics of these patients.

Results of Direct Coronary-Artery Surgery for the Treatment of Angina Pectoris

Abstract One hundred and two consecutive patients undergoing direct coronary surgery for the treatment of stable angina pectoris were evaluated extensively an average of 11.5 months after operation...

The effects of ergonovine maleate on coronary arterial size.

Changes in coronary arterial size due to ergonovine maleate are described and quantitated in 90 patients - 18 with typical angina pectoris, 56 with atypical chest pain, nine with variant angina pectoris, and seven heart transplant (allograft) recipients. We observed two angiographic changes in the diameter of coronary arteries: 1) spasm, which was characterized by occlusion or marked (>85%) focal or diffuse vessel narrowing, or 2) relatively mild and diffuse vessel narrowing, which was interpreted as the normal pharmacologic response to the drug. Serial bolus injections of 0.05 mg, 0.10 mg and 0.25 mg of ergonovine maleate produced diffuse narrowing of the diameter of coronary arteries of 10 ± 1.5%, 16 ± 1.4% and 20 ± 1.3% (mean ± SEM), respectively, in the 72 patients with anginal syndromes who did not develop coronary spasm. The degree of coronary arterial narrowing was the same in heart transplant recipients and in patients with normally innervated hearts who did not develop coronary spasm. We believe the normal pharmacologic response to ergonovine maleate was due to a direct vasoconstrictor action of the drug; this action was independent of neural control extrinsic to the heart.

Coronary artery calcium screening: current status and recommendations from the European Society of Cardiac Radiology and North American Society for Cardiovascular Imaging

Current guidelines and literature on screening for coronary artery calcium for cardiac risk assessment are reviewed for both general and special populations. It is shown that for both general and special populations a zero score excludes most clinically relevant coronary artery disease. The importance of standardization of coronary artery calcium measurements by multi-detector CT is discussed.

Frequency and mechanism of bradycardia in cardiac transplant recipients and need for pacemakers

Orthotopic cardiac transplantation is occasionally complicated by unexplained bradyarrhythmias. Sinus node injury as a consequence of operation or acute rejection has anecdotally been linked to the development of bradycardia early after transplantation. These arrhythmias are empirically managed by pacemaker implantation, the indications for which remain poorly defined. This retrospective study examined the 20-year experience of our institution with bradyarrhythmias after transplantation to determine the predisposing factors and indications for pacemaker implantation. Forty-one of 556 patients in our cardiac transplant program (7.4%) received permanent pacemakers between 1969 and 1989. The predominant rhythm disturbances were junctional rhythm (46%), sinus arrest (27%) and sinus bradycardia (17%). Most patients were asymptomatic (61%), and presented in the early post-transplant period (73%). Four possible predisposing factors were evaluated: (1) graft ischemic time, (2) rejection history, (3) use of bradycardia-inducing drugs, and (4) anatomy of blood supply to the sinoatrial (SA) node. No significant differences existed between patients with and without pacemakers with regard to the first 3 variables. However, after transplantation angiograms showed that prevalence of abnormal SA nodal arteries was greater in patients with than without pacemakers (p less than 0.02). Pacemaker follow-up at 3, 6 and 12 months showed persistent bradycardia (60 to 90 beats/min) in 88, 75 and 50% of patients, respectively. The most common pacemaker complication (15%) was lead displacement at time of biopsy. These results suggest that disruption of the SA nodal blood supply may be an important predisposing factor in the development of bradycardias.

Long-term serial angiographic studies after coronary artery bypass surgery.

Twenty-six patients underwent repeat coronary angiography 5-8 years after saphenous vein coronary artery bypass surgery (SVCABG). These patients were selected from the first cohort of 117 patients who had SVCABG because they had obtained essentially complete relief of angina, and because all grafts were patent at initial angiography 11.2 months (mean) after surgery. Of the 39 grafts (1.5 grafts per patient) patent at 1 year, 34 (87.2%) were patent at reexamination 76 months (mean) (range 65-103 months) after SVCABG. Graft occlusion could not be predicted by the early angiographic appearance of the graft itself or its proximal or distal anastomosis. In some cases, narrowing or irregularity consistent with intimal hyperplasia appeared to progress, while in others it developed at late follow-up. Progressive narrowing occurred in 96% (22 of 23 grafted vessels) of the native coronary arteries proximal to the graft anastomosis. Progression to a stenosis ⩽75% or total occlusion was seen distal to the graft anastomosis in eight of 39 grafts (20%). Of 103 nonbypassed major vessels, 56% showed some progression of disease and half of these progressed to significant stenoses (⩽75% luminal narrowing). There were no apparent predictors to indicate whether progression in nongrafted coronary arteries would occur preferentially in a previously stenotic or nonstenotic vessel, although 80% of vessels with initial stenoses ⩽75% progressed to total occlusion.