Effects of diltiazem, metoprolol, enalapril and hydrochlorothiazide on frequency of ventricular premature complexes

Premature Ventricular Contractions (PVCs): A Narrative Review

Premature ventricular complexes/contractions (PVCs) are relatively common, occurring in 3%-20% of the general population, and are often found during work-up of palpitations or incidentally on routine electrocardiographic testing. They are usually considered benign but can be a sign of underlying cardiac disease and cause significantly impairing symptoms. While often thought of as a problem for the cardiologist, it is not uncommon for PVCs to be identified initially in a primary care or inpatient general medicine setting. This paper will review etiologies, epidemiology, evaluation, and management of PVCs for the internist.

Losartan controlled blood pressure and reduced left ventricular hypertrophy but did not alter arrhythmias in hypertensive men with preserved systolic function

The effect of antihypertensive therapy on arrhythmias is controversial. An initial study in patients with chronic heart failure indicated that losartan, an angiotensin II receptor antagonist, may possess antiarrhythmic properties. However, the effect of AT1 receptor antagonists on arrhythmias of subjects with good systolic function has never been evaluated. Thirty-nine men with primary hypertension (18 without left ventricular hypertrophy [LVH], and 21 with LVH, aged 48.2 +/-8.6 and 50.5 +/-6.0 years, respectively), 15 healthy normotensive subjects (47.9 +/-8.5 years), and 14 highly trained athletes (34.1 +/-1.6 years) were studied. Transthoracic echocardiography and 24-hour Holter ambulatory monitoring were performed at baseline (without treatment). Hypertensive patients underwent the same examinations after 8 months of losartan administration. The prevalence and complexity of ventricular arrhythmias, and the frequency of supraventricular arrhythmias were increased in hypertensive patients with LVH compared to normotensive controls and athletes, at baseline. A similar significant reduction of blood pressure (BP) was noted in both groups of patients (p < 0.001). The LVH was reduced in hypertensives with LVH (the left ventricular mass index by 12%, the interventricular septum by 8.1%, the posterior wall by 7%, all p < 0.01). However, the arrhythmias did not change in either group of patients, even if all hypertensives were considered as 1 group. In conclusion, an 8-month course with losartan was effective in lowering BP and reducing LVH. However, the increased arrhythmias, which were registered in hypertensive patients with LVH at baseline, did not change.

The actions of talinolol, a beta 1-selective beta blocker, in cardiac arrhythmia and acute myocardial infarction

It has long been known that beta-receptor blocking agents, including mainly cardioselective compounds, have favourable effects on tachyarrhythmias of various origins. They are the only substances known so far in the post-infarction phase to reduce significantly sudden cardiac deaths and to lower the rate of recurrent infarctions. High-risk patients seem to benefit most from the application of cardioselective beta blockers. In the acute infarction phase as well, beta-receptor blockers display favourable effects in the majority of patients, especially as they reduce the myocardial-infarct size and lower the tendency to arrhythmias by protecting the heart from sympathetic stimulation. The favourable effect on the variability of the heart rate must be stressed. Furthermore, the early application of beta-receptor blockers is recommended today not only in the event of hyperkinetic reactivity, but also and particularly in so-called high-risk patients, although always respecting the contra-indication. In these patients, mortality is reduced markedly in the long-term treatment.