Biventricular pacing in the early postoperative period after cardiac surgery.

Cardiac resynchronization therapy is not commonly used in the early postoperative period in patients undergoing cardiac surgery who have left ventricular (LV) dysfunction and a history of heart failure. We performed a prospective randomized clinical trial to compare atrial synchronous right ventricular (DDD RV) and biventricular (DDD BIV) pacing within 72 hours after cardiac surgery in patients with an EF ≤35 %, a QRS interval longer than 120 msec and who had LV dyssynchrony detected by real-time three-dimensional echocardiography (RT3DE). Epicardial pacing was provided by a modified Medtronic INSYNC III pacemaker. An LV epicardial pacing lead was implanted on the latest activated segment of the LV based on RT3DE. The study included 18 patients with ischemic heart disease, with or without valvular heart disease (14 men, 4 women, average age 71 years). Patients undergoing DDD BIV pacing had a statistically significant greater CO and CI (CO 6.7±1.8 l/min, CI 3.4±0.7 l/min/m(2)) than patients undergoing DDD RV pacing (CO 5.5±1.4 l/min, CI 2.8±0.7 l/min/m(2)), p<0.001. DDD BIV pacing in the early postoperative period after cardiac surgery corrects LV dyssynchrony and has better hemodynamic results than DDD RV pacing.

[Echocardiographic orientation evaluation of the function of the left heart ventricle]. / Echokardiografické orientacní hodnocení funkce levé komory srdecní.

The authors discuss the possibility to make use of a simple echocardiographic indicator of left ventricular function--the angle formed by the anterior cusp of the mitral valve and the line of the interventricular septum, assessed from a four-chamber tracing (angle M). Based on echocardiographic examination of 87 subjects they established their own standards. They consider values above 30 degrees as pathological, suggesting impaired left ventricular function. The M angle correlates significantly with invasive (final diastolic pressure in the left ventricle, ejection fraction) and with non-invasive (top speed of shortening of the circumferential fibre) indicators of left ventricular function. The authors assume that this simple, quick screening of left ventricular function will prove helpful, in particular in subjects where visualization by one-dimensional echocardiography from a parasternal approach is difficult. In practice it can be also applied for evaluation of left ventricular function during loads, in particular in dynamic echocardiography.