Purpose: The effects of beta-blockers on severe heart failure are not well known. We investigated the effects of carvedilol (beta 1, beta 2, alpha 1-blocker) on symptoms, functional class (FC), and left ventricular function in patients with refractory heart failure.
Methods: We studied 21 patients, mean age 56 +/- 10 years, 9 in FC IV, e 12 in FC III (intermittently with class IV). The initial dosage was 6.25 mg, and it was increased progressively as tolerated. The mean dose was 42 +/- 11 mg. The patients were submitted to routine clinical evaluation, and electrocardiogram. We determined after 196 +/- 60 days of follow-up the left ventricular end diastolic dimension (by echocardiogram), and left ventricular ejection fraction (using MUGA).
Results: Carvedilol was well tolerated by 16 (76%) patients. One patient is in FC II during increment of the dosage. Eight patients were in FC I, and 7 in FC II at 196 +/- 60 days of follow-up. Heart rate decreased from 96 +/- 15 to 67 +/- 10 bpm (p < 0.0001), left ventricular end diastolic diameter from 73 +/- 13 to 66 +/- 12 mm (p < 0.009), and the left ventricular ejection fraction increased from 0.21 +/- 0.06 to 0.34 +/- 0.12 (p < 0.0003).
Conclusion: Carvedilol may have beneficial effects on cardiac function, remodeling process, and FC. If tolerated, it seems to be a potential alternative option in the medical treatment of refractory heart failure. However, investigations are still necessary to clarify the long-term effects of carvedilol on this specific subgroup of patients.