Systolic dysfunction
Systolic dysfunction |
Overview
Left ventricular systolic dysfunction is the condition where the left ventricle can only manage to eject less than 40% (occasionally less than 35%) of the blood in it, with each contraction. The term is used when the echocardiogram shows this but the patient isn’t in overt heart failure.
Diagnosis
Treatment
Pharmacotherapy
For patients with systolic dysfunction (EF < 40%) who have no contraindications:
- ACE (angiotensin-converting enzyme) inhibitors for all patients.
- Beta blockers for all patients except those who are hemodynamically unstable, or those who have rest dyspnea with signs of congestion.
- Aldosterone antagonist (low dose) for patients with rest dyspnea or with a history of rest dyspnea or for symptomatic patients who have suffered a recent myocardial infarction.
- Isordil-hydralazine combination for symptomatic heart failure patients who are African-American.
- ARBs (angiotensin receptor blockers) as a substitute for patients intolerant of ACE inhibitors.
- Digoxin only for patients who remain symptomatic despite diuretics, ACE inhibitors and beta blockers or for those in atrial fibrillation.
- Diuretics for symptomatic patients to maintain appropriate fluid balance.
Device based therapy
- Implantable defibrillators considered for prophylaxis against sudden cardiac death in patients with EF ≤ 35%.
- Bi-ventricular pacemakers considered for patients requiring defibrillators who have symptomatic HF and QRS durations ≥ 120 msec.
References
Additional Readings
- Shekelle P, Rich M, Morton S, et al. Pharmacologic Management of Heart Failure and Left Ventricular Systolic Dysfunction: Effect in Female, Black, and Diabetic Patients, and Cost-Effectiveness. Evidence Report/Technology Assessment No. 82 (Prepared by the Southern California-RAND Evidence-based Practice Center under Contract No 290-97-0001). AHRQ Publication No. 03-E045. Rockville, MD: Agency for Healthcare Research and Quality. July 2003
- McAlister FA, Ezekowitz J, Dryden DM, Hooton N, Vandermeer B, Friesen C, Spooner C, Rowe BH. Cardiac Resynchronization Therapy and Implantable Cardiac Defibrillators in Left Ventricular Systolic Dysfunction. Evidence Report/Technology Assessment No. 152 (Prepared by the University of Alberta Evidence-based Practice Center under Contract No. 290-02-0023). AHRQ Publication No. 07-E009. Rockville, MD: Agency for Healthcare Research and Quality. June 2007.