Surgical ventricular reconstruction for heart failure

Surgical ventricular reconstruction is a technique which has been developed to reconstruct dysfunctional myocardial segments; it is usually performed in conjunction with coronary artery bypass grafting (CABG). Previous studies of this technique have not been randomised and have been limited to observational studies.

STICH (Surgical Treatment for Ischaemic Heart Failure Trial) was a multi-centre, non-blinded, randomised trial conducted at 127 sites in 26 countries. There were 2 major hypotheses. The Hypothesis 1 substudy compared medical therapy and CABG with medical therapy alone and has not yet reported. The Hypothesis 2 substudy compared CABG alone with the combined procedure of CABG and ventricular reconstruction. 1000 patients were recruited from 96 medical centres in 23 countries. Patients were required to have coronary disease amenable to CABG, LVEF <35% and a dominant area of anterior myocardial akinesia or dyskinesia that was suitable for treatment with surgical ventricular reconstruction. All patients received standard medical and device therapy for heart failure.

Major peri-operative events and specified end-points were recorded at discharge or 30 days for patients still in hospital. The primary outcome was time to death from any causes or hospitalisation for cardiac causes. Secondary outcomes included death from any cause at 30 days, hospitalisation for any cause and for cardiovascular causes, myocardial infarction and stroke.

499 patients underwent CABG and 501 underwent the combined procedure of CABG and ventricular reconstruction. The median follow up was for 48 months. Surgical ventricular reconstruction reduced the end systolic volume index by 19% as compared with a reduction of 6% with CABG alone. Cardiac symptoms and exercise tolerance improved form baseline to a similar degree in the two groups. No significant difference was seen in the primary outcome which occurred in 292 (59%) patients undergoing CABG and 289 (58%) undergoing CABG with surgical ventricular reconstruction (hazard ratio for the combined approach 0.99, 95%CI 0.84-1.17, p = 0.90).

This large trial had some key strengths including the use of up-to-date surgical techniques and an attempt to standardise heart failure therapies according to guidelines throughout the entire study population. However there are some important limitations. Whilst the authors state that use of evidence based pharmacological and device therapies was monitored throughout the study, no information is given about rates of use of these over the time of the study. There was a greater reduction in the end systolic volume index with the combined procedure (16ml/m2 body surface area) compared to CABG alone (5ml/m2 body surface area) but these data were only obtained from 373 patients at baseline and at 4 months. More complete and longitudinal information on the end systolic volume index might have provided supporting evidence as to whether ongoing ventricular modelling did occur. Potential explanations for the lack of added efficacy of the combined procedure include the fact that the available heart failure therapies are effective at limiting adverse remodelling. Revascularisation with CABG may enhance this process resulting in a lack of any additional benefit being seen with surgical ventricular reconstruction. When the Hypothesis 1 substudy reports it is hoped that this will provide further insights into the benefits of medical therapies.

  • Jones RH, Velazquez EJ, Michler RE et al. Coronary Bypass Surgery with or without Surgical Ventricular Reconstruction. N Engl J Med 2009;360:1705-17
  • Eisen HJ (ed). Surgical Ventricular Reconstruction for Heart Failure. N Engl J Med 2009;360:1781-4

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