Faculty Bibliography

Recent studies have shown that beta-blockers in patients with hypertension is associated with an increased risk of cardiovascular events, in particular stroke, leading to headlines speculating the end of the beta-blocker era. The objective of this review is to critically examine the usefulness of beta-blockers in cardiovascular diseases. We reviewed the currently available evidence for the usefulness of beta-blockers in patients with hypertension and also assessed the efficacy of its use for other indications, like, chronic heart failure, stable angina, myocardial infarction, arrhythmias etc. The review of the currently available literature shows that for patients with uncomplicated hypertension, there is paucity of data or absence of evidence to support use of beta-blockers as monotherapy or as first line agent. Given the risk of stroke and numerous unacceptable adverse effects, the risk benefit ratio for beta-blockers is not acceptable for this indication. However, beta-blockers are very efficacious agents for the treatment of heart failure, certain types of arrhythmia, and post myocardial infarction. The various guideline committees should seriously reconsider their decision about their endorsement of beta-blockers as first line therapy for uncomplicated hypertension. However, this is applicable for hypertension and beta-blockers continue to be efficacious for other indications

BACKGROUND: The role of coronary artery collaterals in transient ischemic left ventricular (LV) dilatation (TID) during stress echocardiography is not well defined. HYPOTHESIS: Transient ischemic LV dilatation is a marker for extensive and severe coronary artery disease and represents patients without good collaterals. METHODS: We evaluated 212 consecutive patients (57 +/- 16 years, 70% male) who had coronary angiography and stress echocardiography within a 3-month period. This cohort of patients was divided into three groups based on type of collaterals: Group A: no collaterals; Group B: collaterals supplied by vessels without flow-limiting stenosis (good collaterals); Group C: collaterals supplied by vessels with flow-limiting stenosis (bad/jeopardized collaterals). In all patients, angiographic jeopardy score (AJS), ejection fraction (EF), and wall motion score index (WMSI) at rest and during stress were evaluated. Transient ischemic LV dilatation was defined as transient increase in the end-systolic dimensions from rest to peak stress. RESULTS: Transient ischemic LV dilatation was present in 42 (20%) patients. Patients with TID had a lower EF, higher AJS, greater number of ischemic segments, and higher peak WMSI. Patients with TID in Group A (no collaterals) and Group C (jeopardized collaterals) had a greater percentage of multivessel disease than those in Group B (good collaterals). Presence of Group A or Group C collaterals was a predictor of TID even after controlling for multivessel disease, rest and peak WMSI, and left anterior descending artery disease. CONCLUSIONS: Transient ischemic LV dilatation on stress echocardiography is a marker for extensive and severe coronary artery disease and represents patients with angiographically absent collaterals or those with jeopardized coronary collaterals

BACKGROUND: Patients with prior myocardial infarction (MI) are at increased risk of subsequent cardiac events (MI or cardiac death). The incremental prognostic value and warranty time of a normal stress echocardiogram in this high-risk population is not well defined. METHODS: We evaluated 251 consecutive patients (62 +/- 11 years; 64% males) with remote history of MI (>6 weeks) undergoing stress echocardiography (83% dobutamine). Ischemia was defined as a new reversible wall motion abnormality and/or biphasic response. Follow-up for up to 4 years (mean 2.9 +/- 1.0 years) for confirmed MI (n = 7) and cardiac death (n = 15) were obtained. RESULTS: Stress echocardiography effectively risk stratified patients into normal versus abnormal subgroups (Event rate 0.8% per year vs 4.2% per year; P = 0.01; RR = 5.6, 95% CI = 1.3-24.7). In patients with a normal stress echocardiogram, the event rate at the end of 6, 12, and 18 months were <1% per year. After 18 months the event rate in patients with a normal stress echocardiogram increased greatly (>1% per year). Stress echocardiography yields incremental prognostic value over clinical and stress electrocardiographic variables (Global chi-square increased from 12.4 to 25 to 31.1, P < 0.0001 both groups). CONCLUSIONS: Stress echocardiography yields appropriate risk stratification and prognosis and provides incremental prognostic value over clinical and stress electrocardiographic variables even in patients with prior MI. A normal stress echocardiogram portends a benign prognosis (<1% event rate/year) for up to 18 months