Marisa Di Donato

Akinetic versus dyskinetic postinfarction scar: relation to surgical outcome in patients undergoing endoventricular circular patch plasty repair.

OBJECTIVES This retrospective study attempted to relate surgical outcome with the extent and type of preoperative wall motion asynergy in patients with postinfarction myocardial scar who underwent endoventricular circular patch plasty repair and associated coronary grafting. BACKGROUND Left ventricular (LV) pump function improvement is difficult to predict after aneurysmectomy, for either akinetic or dyskinetic scar, and previous studies have reported that the absence of paradoxic systolic motion correlates with higher operative mortality and no improvement in pump function. METHODS Two hundred forty-five patients who underwent endoventricular circular patch plasty repair and associated coronary grafting were retrospectively selected if they had technically adequate right and left anterior LV angiograms before the operation. All had right and left cardiac catheterization. The centerline method was applied to preoperative right anterior oblique LV angiography to assess the absolute motion of the chords and the percent length of the perimeter showing a fractional shortening <2 SD from the normal mean value (extent of asynergy ([A%]). RESULTS The overall perioperative mortality rate was 6%; 120 patients had akinetic and 125 had dyskinetic scar, and no differences were found among the groups in terms of all the clinical and hemodynamic variables collected in the study. Patients with a large scar (A% >60), either akinetic or dyskinetic, had a higher perioperative mortality rate (12%) than patients with a small scar (2.2%). After the operation, the ejection fraction (EF) increased from 36 +/- 13% to 50 +/- 13% (mean +/- SD), and pulmonary pressures significantly decreased. End-diastolic volume decreased from 199 +/- 75 to 89 +/- 36 ml/m2. Patients with a large akinetic scar had the most severely impaired preoperative function (largest ventricular volumes and highest pulmonary mean pressure); nevertheless, they had an impressive improvement in function (EF from 25 +/- 9% to 41 +/- 12%), not different from that observed with large dyskinetic scarring (EF from 26 +/- 7% to 46 +/- 11%). CONCLUSIONS Surgical outcome of endoventricular circular patch plasty repair for postinfarction myocardial scar relates to the extent of LV asynergy rather than to the presence or absence of dyskinesia. Patients with a large akinetic scar and severely depressed pump function benefit from a relatively simple surgical procedure previously reserved only for dyskinetic aneurysm. The reduction of wall tension and oxygen demand, owing to the marked decrease of volumes, and the increase in oxygen supply, owing to revascularization, may play a major role in improving pump function.

MicroRNA Dysregulation in Diabetic Ischemic Heart Failure Patients

Increased morbidity and mortality associated with ischemic heart failure (HF) in type 2 diabetic patients requires a deeper understanding of the underpinning pathogenetic mechanisms. Given the implication of microRNAs (miRNAs) in HF, we investigated their regulation and potential role. miRNA expression profiles were measured in left ventricle biopsies from 10 diabetic HF (D-HF) and 19 nondiabetic HF (ND-HF) patients affected by non–end stage dilated ischemic cardiomyopathy. The HF groups were compared with each other and with 16 matched nondiabetic, non-HF control subjects. A total of 17 miRNAs were modulated in D-HF and/or ND-HF patients when compared with control subjects. miR-216a, strongly increased in both D-HF and ND-HF patients, negatively correlated with left ventricular ejection fraction. Six miRNAs were differently expressed when comparing D-HF and ND-HF patients: miR-34b, miR-34c, miR-199b, miR-210, miR-650, and miR-223. Bioinformatic analysis of their modulated targets showed the enrichment of cardiac dysfunctions and HF categories. Moreover, the hypoxia-inducible factor pathway was activated in the noninfarcted, vital myocardium of D-HF compared with ND-HF patients, indicating a dysregulation of the hypoxia response mechanisms. Accordingly, miR-199a, miR-199b, and miR-210 were modulated by hypoxia and high glucose in cardiomyocytes and endothelial cells cultured in vitro. In conclusion, these findings show a dysregulation of miRNAs in HF, shedding light on the specific disease mechanisms differentiating diabetic patients.

Surgical Ventricular Restoration Improves Mechanical Intraventricular Dyssynchrony in Ischemic Cardiomyopathy

Background—In ischemic cardiomyopathy, dyssynchrony of left ventricular (LV) mechanical contraction produces adverse hemodynamic consequences. This study tests the capacity of geometric rebuilding by surgical ventricular restoration (SVR) to restore a more synchronous contractile pattern after a mechanical, rather than electrical, intervention. Methods and Results—A prospective study of the global and regional components of dyssynchrony was conducted in 30 patients (58±8 years of age) undergoing SVR at the Cardiothoracic Center of Monaco. The protocol used simultaneous measurements of ventricular volumes and pressure to construct pressure/volume (P/V) and pressure/length (P/L) loops. Angiograms were done before and after SVR to study a 600-ms cycle during atrial pacing at 100 bpm. Mean QRS duration was similar, at 100±17 ms preoperatively and 114±28 ms postoperatively (NS). Preoperative LV contraction was highly asynchronous, because P/V loops showed abnormal isometric phases with a right shifting. Endocardial time motion was either early or delayed at the end-systolic phase so that P/L loops were markedly abnormal in size, shape, and orientation. Postoperatively, SVR resulted in leftward shifting of P/V loops and increased area; endocardial time motion and P/L loops almost normalized to allow a better contribution of single regions to global ejection. The hemodynamic consequences of SVR were improved ejection fraction (30±13% to 45±12%; P =0.001); reduced end-diastolic and end-systolic volume index (202±76 to 122±48 and 144±69 to 69±40 mL/m2; P =0.001); more rapid peak filling rate (1.75±0.7 to 2.32±0.7 EDV/s; P =0.0001); peak ejection rate (1.7±0.7 to 2.6±0.9 Sv/s; P =0.0002), and mechanical efficiency (0.56±0.15 to 0.65±0.18; P =0.04). Conclusions—SVR produces a mechanical intraventricular resynchronization that improves LV performance.

Surgical Ventricular Restoration: The RESTORE Group Experience

Congestive heart failure may be caused by late left ventricular (LV) dilation following anterior infarction. Early reperfusion prevents transmural necrosis, and makes the infarcted segment akinetic rather than dyskinetic. Surgical ventricular restoration (SVR) reduces LV volume and creates a more elliptical chamber by excluding scar in either akinetic or dyskinetic segments.The international RESTORE group applied SVR in a registry of 1198 post-infarction patients between 1998 and 2003. Early and late outcomes were examined and risk factors identified.Concomitant procedures included coronary artery bypass grafting in 95%, mitral valve repair in 22%, and mitral valve replacement in 1%. Overall 30-day mortality after SVR was 5.3% (8.7% with mitral repair vs. 4.0% without repair, p < .001) Perioperative mechanical support was uncommon (< 9%).Global systolic function improved postoperatively, as ejection fraction increased from 29.6 ± 11.0% to 39.5 ± 12.3% (p < .001) and left ventricular end systolic volume index decreased from 80.4 ± 51.4 ml/m2 to 56.6 ± 34.3 ml/m2 (p < .001). Overall 5-year survival was 68.6 ± 2.8%, Logistic regression analysis identified EF ≤ 30%, LVESVI ≥ 80 ml/m2, advanced NYHA functional class, and age ≥75 years as risk factors for death. Five-year freedom from hospital readmission for CHF was 78%. Preoperatively, 67% of patients were class III or IV, and postoperatively 85% were class I or II.SVR improves ventricular function and is highly effective therapy in the treatment of ischemic cardiomyopathy with excellent 5-year outcome.

Outcome of left ventricular aneurysmectomy with patch repair in patients with severely depressed pump function

To determine the efficacy of left ventricular (LV) aneurysm resection and endoventricular patch repair with septal exclusion in patients with severely depressed pump function, we retrospectively selected 62 patients (mean age 59 +/- 7 years) with preoperative LV ejection fraction < or = 20%, from a series of 322 patients with postinfarction LV aneurysm who underwent this type of surgery at our center during a 5-year period. Mean ejection fraction was 17 +/- 3%; all patients were in New York Heart Association (NYHA) class III/IV, and all had hemodynamic and electrophysiologic studies before and after surgery. We analyzed both operative and long-term survival, and hemodynamic, electrophysiologic, and angiographic variables, as well as the symptomatic state after surgery. Follow-up was available in all patients (mean 23 +/- 14 months). Subtotal endocardiectomy and cryotherapy were associated in patients presenting with spontaneous or inducible ventricular arrhythmias (VA). Hospital mortality rate was 19.3%. Ejection fraction improved from 17 +/- 3% to 37 +/- 10% (p < 0.001); ventricular arrhythmias decreased significantly after surgery. Factors influencing early mortality at multivariate analysis were the presence of critical lesions on the circumflex artery and the duration of cardiopulmonary bypass. At 1-year control, a significant reduction in NYHA class was observed and no patient was in NYHA class IV. The improvement in ejection fraction was maintained (39 +/- 11%), as well as the reduction in inducible and spontaneous ventricular arrhythmias. There were 5 late deaths at follow-up, accounting for a late mortality of 10% at 5 years.

End-systolic volume following surgical ventricular reconstruction impacts survival in patients with ischaemic dilated cardiomyopathy

A left ventricular end‐systolic volume (LVESV) ≥60 mL/m2 has been shown to be associated with increased cardiac mortality after a reperfused myocardial infarction (MI). The reduction in LVESV following surgical ventricular reconstruction (SVR) is reported to be between 19% and 50% but its impact on prognosis is not well‐established. The aim of this study was therefore to assess the impact on survival of a residual LVESV index (LVESVI) of ≥ or <60 mL/m2 following SVR.

Insights from the STICH trial: change in left ventricular size after coronary artery bypass grafting with and without surgical ventricular reconstruction.

OBJECTIVE The present analysis of the Surgical Treatment for Ischemic Heart Failure randomized trial data examined the left ventricular volumes at baseline and 4 months after surgery to determine whether any magnitude of postoperative reduction in end-systolic volume affected survival after coronary artery bypass grafting alone compared with bypass grafting plus surgical ventricular reconstruction. METHODS Of the 1000 patients randomized, 555 underwent an operation and had a paired imaging assessment with the same modality at baseline and 4 months postoperatively. Of the remaining 455 patients, 424 either died before the 4-month study or did not have paired imaging tests and were excluded, and 21 were not considered because they had died before surgery or did not receive surgery. RESULTS Surgical ventricular reconstruction resulted in improved survival compared with coronary artery bypass grafting alone when the postoperative end-systolic volume index was 70 mL/m(2) or less. However, the opposite was true for patients achieving a postoperative volume index greater than 70 mL/m(2). A reduction in the end-systolic volume index of 30% or more compared with baseline was an infrequent event in both treatment groups and did not produce a statistically significant survival benefit with ventricular reconstruction. CONCLUSIONS In patients undergoing coronary artery bypass grafting plus surgical ventricular reconstruction, a survival benefit was realized compared with bypass alone, with the achievement of a postoperative end-systolic volume index of 70 mL/m(2) or less. Extensive ventricular remodeling at baseline might limit the ability of ventricular reconstruction to achieve a sufficient reduction in volume and clinical benefit.

Aortic Valve Replacement in Octogenarians: Is Biologic Valve the Unique Solution?

BACKGROUND This study analyzed morbidity, mortality, and quality of life after aortic valve replacement with mechanical and biologic prostheses in octogenarian patients. METHODS A retrospective analysis was performed in 345 consecutive patients, mean age of 82 +/- 2 years (range, 80 to 92), who had aortic valve replacement from May 1991 to April 2005. A bioprosthesis (group I) was used in 200 patients (58%), and 145 (42%) received a mechanical prosthesis (group II). Associated cardiac procedures were done in 211 patients (61%), of which 71% were coronary artery bypass grafting. Patients had symptomatic aortic stenosis (84.3%) or associated aortic insufficiency; 88% were in New York Heart Association (NYHA) class III or IV. The mean preoperative aortic valve gradient was 62 +/- 16 mm Hg (range, 25 to 122 mm Hg). The mean left ventricular ejection fraction was good (0.52 +/- 0.12); 30 patients (8.7%) had an ejection fraction of less than 0.30. RESULTS The in-hospital mortality rate was 7.5% (26 patients); 17 (8.5%) in group I and 9 (6.2%) in group II (p = 0.536) Significant predictors of operative mortality were preoperative renal insufficiency (blood creatinine > 2.00 mg/mL) and need for urgent operation. Mean follow-up, complete at 100%, was 40 +/- 33 months (range, 1 to 176 months). Long-term follow-up, using Kaplan-Meier analysis, showed an overall survival of 61% at 5 years and 21% at 10 years; survival by type of prosthesis was significantly higher with mechanical prostheses (log-rank p = 0.03). Freedom from cerebrovascular events (thromboembolic/hemorrhagic) at 5 and 10 years was 89% and 62% in the mechanical group and 92% and 77% in the biologic group (p = 0.76). Postoperative NYHA functional class was I or II in 96% of patients. Quality-of-life scores were excellent considering the age of the patients. No differences were found between the two groups. CONCLUSIONS Surgical treatment for symptomatic aortic stenosis in octogenarians has an acceptable operative risk with excellent long-term results and good quality of life. In this cohort, survival rate is slightly but significantly higher with mechanical prostheses.

Surgical ventricular restoration: left ventricular shape influence on cardiac function, clinical status, and survival.

BACKGROUND Myocardial infarction can result in a spectrum of left ventricular (LV) shape abnormalities. Surgical ventricular restoration (SVR) can be applied to any, but there are no data that relate its effectiveness to LV shape. Moreover, there is no consensus on the benefit of SVR in patients with a markedly dilated ventricle, without clear demarcation between scarred and normal tissue. This study describes postmyocardial infarction shape abnormalities and cardiac function, clinical status, and survival in patients undergoing SVR. METHODS Echo studies of 178 patients were retrospectively reviewed. Three types of LV shape abnormalities were identified: type 1 (true aneurysm), type 2 (nonaneurysmal lesions defined as intermediate cardiomyopathy), and type 3 (ischemic dilated cardiomyopathy). RESULTS SVR induced significant improvement in cardiac and clinical status in all patients, regardless LV shape types. Although not significant, mortality was higher in types 2 and 3. CONCLUSIONS Ischemic dilated cardiomyopathy and not just the true aneurysm can be successfully treated with SVR. Shape classification may be useful to improve patient selection and compare results from different institutions that are otherwise impossible to compare.

Impact of Surgical Ventricular Restoration on Diastolic Function: Implications of Shape and Residual Ventricular Size

BACKGROUND Limited data are available on left ventricle (LV) diastolic function in patients with ischemic dilated cardiomyopathy submitted to surgical ventricular restoration (SVR). The purpose of this study was to assess postoperative diastolic function changes and identify potential predictors of its worsening. METHODS One hundred and forty-six patients (65 +/- 9 years) with previous anterior myocardial infarction were evaluated before and after SVR. Hemodynamic and geometric parameters including the sphericity index and conicity index were measured. Diastolic function was explored using the transmitral flow velocity pattern, and four classes were defined: normal, abnormal relaxation, pseudonormal, and restrictive pattern. Diastolic function was defined as unchanged (no difference in diastolic pattern), improved (at least one class less), or worsened (at least one class more or, in the case of preoperative restrictive pattern, an early transmitral flow velocity to atrial flow velocity [E/A] ratio increase of at least 20%). RESULTS The filling pattern before SVR was normal in 7 patients (4.8%), abnormal relaxation in 99 (68%), pseudonormal in 28 (19%), and restrictive in 12 (8.2%). After SVR, the filling pattern was unchanged in 105 patients (72%), improved in 14 (9.6%), and worsened in 27 (18.4%). Based on the univariate analysis, the preoperative conicity index and the end-diastolic volume difference (the result of surgical volume reduction) were associated with a diastolic pattern worsening. CONCLUSIONS Diastolic function did not change or improve in the majority of patients. In the minority of patients who experienced worsening, this was associated with the preoperative LV shape and residual volume.