Prolonged QRS duration (QRS >/=170 ms) and left axis deviation in the presence of left bundle branch block: A marker of poor left ventricular systolic function?

BACKGROUND: Left bundle branch block (LBBB) is commonly associated with structural heart disease and left ventricular dysfunction. We propose that the QRS duration and degree of left-axis deviation (LAD) identify significant left ventricular systolic dysfunction in patients with LBBB. METHODS: In this prospective study the ejection fraction (EF) of 300 consecutive patients with LBBB was evaluated by echocardiography. The relationship between QRS duration and LAD (axis between -30 degrees and -90 degrees ) and EF were derived. RESULTS: There was no significant difference in age, sex, presence of ischemic or nonischemic cardiomyopathy and valvular heart disease, and EF among the patients with or without LAD. The EF of patients with QRS >/=170 milliseconds with LAD (n = 20) and without LAD (n = 18) was 25% +/- 16% and 23% +/- 13%, respectively (P =.71). The mean EF (24% +/- 10%) of the patients with a QRS duration of >/=170 milliseconds (n = 38) was significantly lower than the mean EF (36% +/- 16%) of the patients with a QRS duration of <170 milliseconds (n = 262, P <.015). The QRS duration also had a significant (P <.001) inverse correlation with EF (R = 0.37, adjusted R (2) = 0.13, SE of estimate = 16.21). However, the QRS axis was not significantly correlated with EF and did not have added predictive value. CONCLUSIONS: The QRS duration has a significant inverse relationship with EF and prolongation of QRS duration (>/=170 milliseconds) in the presence of LBBB is a marker of significant left ventricular systolic dysfunction. The presence of LAD in LBBB does not signify a further decrease in EF.

Asymptomatic left ventricular permanent pacemaker malposition detected on routine follow-up--a case report.

The authors present an asymptomatic left ventricular pacemaker lead malposition that was detected upon routine 2-D Echocardiography. Clinical implication diagnosis and therapeutic options on left ventricular pacemaker lead malposition are discussed.

Acute reversible cardiomyopathy and thromboembolism after cisplatin and 5-fluorouracil chemotherapy--a case report.

Acute development of cardiomyopathy and occlusive thromboembolic events following cisplatin and 5-fluorouracil (5-FU) is rare but frequently lethal. The authors report the successful management of such an event in a 52-year-old man with squamous cell carcinoma of the soft palate. The possible pathophysiological mechanisms are discussed.