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Beta blockade in congestive heart failure: persistent adverse haemodynamic effects during chronic treatment with
M L Kukin1, J Kalman, M M Mannino
1Heart Failure Program, Mount Sinai Medical Center, New York, New York 10029, USA. marrick_kukin@SMTPlink.mssm.edu
Insights
Beta blockers like metoprolol show initial benefits for heart failure patients but their acute adverse haemodynamic effects persist with chronic treatment. Subsequent doses worsen cardiac index and stroke work index.
Area of Science:
- Cardiology
- Pharmacology
- Heart Failure Management
Background:
- Congestive heart failure (CHF) management often involves beta-blocker therapy.
- Acute administration of beta-blockers can cause adverse haemodynamic effects in CHF patients.
Purpose of the Study:
- To investigate if the acute negative haemodynamic effects of beta-blockade persist during long-term treatment in patients with congestive heart failure.
Main Methods:
- A sequential haemodynamic evaluation was performed on 26 patients with moderate to severe CHF.
- Patients received escalating doses of metoprolol over three months, with haemodynamic measurements taken at baseline and after treatment.
- Right heart catheterisation was used to assess haemodynamic parameters.
Main Results:
- Chronic metoprolol treatment demonstrated functional, exercise, and haemodynamic benefits, including reduced heart rate and improved cardiac index.
- However, readministration of full-dose metoprolol during chronic treatment led to a significant reduction in cardiac index and stroke work index.
- Systemic vascular resistance significantly increased upon readministration of the full dose.
Conclusions:
- The study concludes that the adverse haemodynamic effects of beta-blockers in heart failure patients are not transient and persist during chronic treatment.
- Worsening haemodynamic indices observed with subsequent doses indicate a sustained negative impact.
Objective:
To determine whether the acute adverse haemodynamic effects of beta blockade in patients with congestive heart failure persist during chronic treatment.
Design:
Sequential haemodynamic evaluation of heart failure patients at baseline and after three months of continuous treatment with the beta 1 selective antagonist metoprolol.
Setting:
Cardiac care unit in university hospital.
Patients:
26 patients with moderate to severe congestive heart failure (New York Heart Association grade II to IV) and background treatment with digoxin, diuretics, and angiotensin converting enzyme inhibitors, and with a left ventricular ejection fraction < 25%.
Methods:
Baseline variables included a six minute walk, maximum oxygen consumption, and right heart catheterisation. All patients received metoprolol 6.25 mg orally twice daily initially and the dose was gradually increased to a target of 50 mg twice daily. Haemodynamic measurements were repeated after three months of treatment, both before (trough) and after drug readministration.
Results:
Long term metoprolol had functional, exercise, and haemodynamic benefits. It produced decreases in heart rate, pulmonary capillary wedge pressure, and systemic vascular resistance, and increases in cardiac index, stroke volume index, and stroke work index. However, when full dose metoprolol was readministered during chronic treatment, there was a reduction in cardiac index (from 2.8 (SD 0.46) to 2.3 (0.38) l/min/m2, p << 0.001) and stroke work index (from 31.4 (11.1) to 26.6 (10.0) g.m/m2, p < 0.001) and an increase in systemic vascular resistance (from 943 (192) to 1160 (219) dyn.s.cm-5, p << 0.001).
Conclusions:
Adverse haemodynamic effects of beta blockers in heart failure persist during chronic treatment, as shown by worsening haemodynamic indices with subsequent doses.