BACKGROUND: Acute left ventricular-based pacing has been shown to improve hemodynamics in patients with severe heart failure and left bundle branch block (LBBB). However, it is not known whether the cause of the underlying heart disease influences the potential effect of left ventricular-based pacing. OBJECTIVES: The aim of this study was to determine whether beneficial hemodynamic effects of acute left ventricular-based pacing in severe chronic heart failure are dependent on underlying heart disease. METHODS: After coronary angiography, patients with severe heart failure and LBBB were separated into two groups: dilated (25 patients; 20 male) and ischemic cardiomyopathy (21 patients; 20 male). Hemodynamic parameters were evaluated at baseline and during left ventricular-based pacing. RESULTS: Improvement in hemodynamic parameters were similar in both groups, during acute left ventricular pacing (changes expressed in percentage): pulmonary capillary wedge pressure, -16+/-15% vs. -14+/-10%; V wave amplitude, -25+/-18% vs. -21+/-17%; and biventricular pacing, -15+/-15% vs. -11+/-11% and -23+/-18% vs. -16+/-18%, respectively. CONCLUSION: Underlying heart disease does not influence the response to acute left ventricular-based pacing in patients with severe heart failure and LBBB. This finding provides support for including all patients with enlarged heart and heart failure in future studies evaluating left ventricular-based pacing.
BACKGROUND: Acute left ventricular-based pacing has been shown to improve hemodynamics in patients with severe heart failure and left bundle branch block (LBBB). However, it is not known whether the cause of the underlying heart disease influences the potential effect of left ventricular-based pacing. OBJECTIVES: The aim of this study was to determine whether beneficial hemodynamic effects of acute left ventricular-based pacing in severe chronic heart failure are dependent on underlying heart disease. METHODS: After coronary angiography, patients with severe heart failure and LBBB were separated into two groups: dilated (25 patients; 20 male) and ischemic cardiomyopathy (21 patients; 20 male). Hemodynamic parameters were evaluated at baseline and during left ventricular-based pacing. RESULTS: Improvement in hemodynamic parameters were similar in both groups, during acute left ventricular pacing (changes expressed in percentage): pulmonary capillary wedge pressure, -16+/-15% vs. -14+/-10%; V wave amplitude, -25+/-18% vs. -21+/-17%; and biventricular pacing, -15+/-15% vs. -11+/-11% and -23+/-18% vs. -16+/-18%, respectively. CONCLUSION: Underlying heart disease does not influence the response to acute left ventricular-based pacing in patients with severe heart failure and LBBB. This finding provides support for including all patients with enlarged heart and heart failure in future studies evaluating left ventricular-based pacing.