Michael E. Assey

Predictors of outcome for aortic valve replacement in patients with aortic regurgitation and left ventricular dysfunction: A change in the measuring stick

Although left ventricular function is generally regarded as a key determinant of prognosis in aortic regurgitation, predictors of outcome of aortic valve replacement based on this factor have recently been questioned. This study was performed to examine the role of indexes of left ventricular function in predicting the outcome of surgery in patients with aortic regurgitation and left ventricular dysfunction. Fourteen patients with aortic regurgitation with a preoperative ejection fraction of less than 0.55 (average 0.45 +/- 0.02) who underwent aortic valve replacement were studied. The patients had 82 (58%) of a possible 140 predictors of negative outcome preoperatively, but 12 of the 14 patients had a decrease in symptoms and an increase in ejection fraction into the normal range after operation (average postoperative ejection fraction 0.59 +/- 0.04). Although improvement occurred despite the presence of many negative predictors of outcome, there was a significant correlation between postoperative ejection fraction and eight of the tested preoperative predictors. Preoperative end-systolic dimension correlated best (r = -0.91) with postoperative ejection fraction. An end-systolic dimension of 60 mm correlated with a postoperative ejection fraction of 0.55. The results indicate that preoperative ventricular function is still an important determinant of outcome of aortic valve replacement for aortic regurgitation. However, current medical and surgical techniques permit a better prognosis in the presence of reduced ventricular function than was previously considered possible.

Incidence of acute myocardial infarction in patients with exercise-induced silent myocardial ischemia

Fifty-five patients with angiographically proved coronary artery disease (CAD) underwent Bruce protocol exercise stress testing with thallium-201 imaging. Twenty-seven patients (group I) showed myocardial hypoperfusion without angina pectoris during stress, which normalized at rest, and 28 patients (group II) had a similar pattern of reversible myocardial hypoperfusion but also had angina during stress. Patients were followed for at least 30 months. Six patients in group I had an acute myocardial infarction (AMI), 3 of whom died, and only 1 patient in group II had an AMI (p = 0.05), and did not die. Silent myocardial ischemia uncovered during exercise stress thallium testing may predispose to subsequent AMI. The presence of silent myocardial ischemia identified in this manner is of prognostic value, independent of angiographic variables such as extent of CAD and left ventricular ejection fraction.

The puzzle of normal coronary arteries in the patient with chest pain: What to do?

Over one million Americans undergo cardiac catheterization each year because of chest pain, with the expectation that coronary artery disease will be found. However, up to 30%—a subgroup that includes patients with both cardiac and noncardiac pathology—will have angiographically normal coronary arteries. While the prognosis of the group as a whole is excellent, successful management requires a clear understanding of the multiple and varied conditions that can cause this syndrome.

Cardiovascular status of panic disorder patients with and without prominent cardiac symptoms

The extent of the cardiovascular evaluation of panic disorder patients with cardiac symptoms remains a dilemma for the clinician. The authors conducted a pilot study to assess the cardiac status of 20 panic disorder patients, 10 of whom had prominent cardiac symptoms and 10 of whom did not. No differences in the cardiac abnormalities were found between the groups. These findings suggest that panic disorder patients with cardiac symptoms are not more likely to have cardiac disease than those without prominent cardiac symptoms. The practical implications of these findings are discussed.

Prognosis in stable angina pectoris and silent myocardial ischemia

The results of current investigation suggest that a former clinical standby, namely, the presence or absence of angina, is no longer the principal prognostic factor for determining a patients risk of cardiac events, including myocardial infarction. In a retrospective analysis, patients with chronic stable angina were compared on the basis of presence or absence of angina during ischemia detected by thallium imaging. Patients were similar in terms of risk factors, clinical characteristics and catheterization data. At 30 months of follow-up, the myocardial infarction rate was 22% in the silent group compared with 4% in the group with angina. Transient asymptomatic ischemia has prognostic value independent of other variables such as exercise stress testing or cardiac catheterization data. Future prognostic studies should be careful to include patient populations with similar characteristics; they also will need to provide protracted follow-up and utilize sensitive and reproducible diagnostic techniques.