April 21st, 2011
Will a STICH in Time Save Nine?
A 57-year-old man with a history of hypertension, hyperlipidemia, and smoking presented with increasing dyspnea on exertion, mild chest discomfort, and lower-extremity edema. Physical exam results were consistent with decompensated heart failure.
- left-ventricular ejection fraction (LVEF), 20%
- LV end-diastolic dimension, 6.3 cm
- global hypokinesis (with regional variation affecting the septum, inferior wall, and apex most severely)
- mildly enlarged right ventricle with moderately reduced function
- mitral annular dilatation with at least moderate mitral regurgitation
- moderate tricuspid regurgitation (estimated pulmonary-artery systolic pressure, 30 mm Hg + right-atrial pressure)
An evaluation for the cause of new-onset cardiomyopathy included a left-heart catheterization that revealed 60% left-main disease and an 80% proximal right coronary artery lesion.
Subsequent myocardial perfusion imaging (with Regadenoson positron-emission tomography) revealed a medium-size perfusion defect throughout the inferior and basal inferoseptal walls with moderate reversibility and a small reversible perfusion defect in the LV apex. The patient’s summed stress score (scar + ischemia) was 11; the summed difference score (ischemia) was 4. His resting LVEF was 16%, with an end-systolic volume index of 96 mL/m2. His post-stress LVEF was 18%, with an end-systolic volume index of 100 mL/m2.
The patient was treated with intravenous diuretics and was started on aspirin and a statin. Once he was euvolemic, a low-dose ACE inhibitor and beta-blockers were added. Amiodarone was started after monitoring revealed several runs of nonsustained ventricular tachycardia.
A right-heart catheterization after medical optimization revealed right-atrial pressure of 4 mm Hg, pulmonary-artery pressure of 41/19 mm Hg, and pulmonary capillary wedge pressure of 13 mm Hg. Pulmonary-artery saturation was 66%, with a calculated cardiac output of 3.1 L/minute and a cardiac index of 1.65 L/minute/m2.
1. Would coronary revascularization benefit this patient? If so, would you recommend that he undergo surgical revascularization specifically?
2. Do findings from the recently published STICH trial influence your assessment? If so, how?
3. If you proceed with surgery, should it be performed at a ventricular assist device/transplant center?
James Fang, MD
This gentleman has received appropriate care up to this point. I would have taken the same approach. If he remains symptomatic (particularly with angina), revascularization can be offered. In some centers, multivessel/left main PCI could even be entertained. It should be pointed out that this patient would not have been eligible for STICH because of the left main disease. However, the overall approach remains consistent with the STICH trial in that patients crossed over from medicine to surgery if it was felt to be clinically necessary. I generally favor the performance of high risk procedures or surgeries in places where advanced support can be offered.
One final comment: the hemodynamics are a bit curious. The calculated cardiac output is relatively low for that pulmonary artery saturation suggesting that either the hgb concentration was very high or the oxygen consumption used in the calculation may not have been accurate.
Anju Nohria, MD
The patient was thought to have a combined ischemic and nonischemic cardiomyopathy. Given his low ejection fraction and left-ventricular dilatation, he was considered to be a high-risk candidate for surgical revascularization without clear expectation of benefit. Therefore, he was medically managed and evaluated for cardiac transplantation.
The only notable finding on the patient’s initial evaluation for transplant was continued tobacco use, and listing for transplantation was deferred until he could demonstrate abstinence from smoking for at least 6 months. His initial peak oxygen uptake was 7.4 mL/kg/minute at an adequate work load. After close follow-up and gradual up-titration of his ACE-inhibitor and beta-blocker dosing, peak oxygen uptake had increased (9 months later) to 13 mL/kg/minute.
The patient continues to exhibit NYHA class III symptoms, and his consent for listing as a Status 2 transplantation candidate is now being sought.