Myocardial revascularization as a therapeutic strategy in the patient with advanced ventricular dysfunction

Early and Mid-Term Outcomes of Patients Undergoing Coronary Artery Bypass Grafting in Ischemic Cardiomyopathy

Background Many observational studies and trials have shown that coronary artery bypass grafting improves the survival in patients with ischemic cardiomyopathy. However, these results are based on data generated from developed countries. Poor socioeconomic statuses, lack of uniformity in healthcare delivery, differences in risk profile, and affordability to access optimal health care are some factors that make the conclusions from these studies irrelevant to patients from India. Methods and Results One-hundred and sixty-two patients with severe left ventricular dysfunction (ejection fraction ≤35%) who underwent coronary artery bypass grafting from 2009 to 2017 were enrolled for this study. Mean age of the study population was 58.67±9.70 years. Operative mortality was 11.62%. Thirty day/in-house composite outcome of stroke and perioperative myocardial infarction were 5.8%. The percentage of survival for 1 year was 86.6%, and 5-year survival was 79.9%. Five-year event-free survival was 49.3%. The mean ejection fraction improved from 30.7±4.08% (range 18-35) to 39.9±8.3% (range 24-60). Lack of improvement of left ventricular function was a strong predictor of late mortality (hazard ratio, 21.41; CI 4.33-105.95). Even though there was a trend towards better early outcome in off-pump CABG , the 5-year survival rates were similar in off-pump and on-pump group (73.4% and 78.9%, respectively; P value 0.356). Conclusions We showed that coronary artery bypass grafting in ischemic cardiomyopathy was associated with high early composite outcomes. However, the 5-year survival rates were good. Lack of improvement of left ventricular function was a strong predictor of late mortality.

Coronary Bypass Surgery in Patients with Pulmonary Hypertension: Assessment of Early and Long Term Results

PURPOSE

We aimed to evaluate the effects of preoperative pulmonary hypertension (PH) on early and long term results in patients undergoing coronary bypass surgery and the effects of coronary bypass surgery on PH.

METHODS

Among 2325 patients who underwent elective isolated coronary artery bypass surgery between March 2003 and March 2012, 287 patients with high preoperative pulmonary arterial pressure (PAP) ≥30 mmHg were examined. Patients' data were obtained by retrospective examination of our clinic's database. 69 patients who had complete parameters included in the study.

RESULTS

There was no increase in the New York Heart Association (NYHA) functional classification 84% of cases. Preoperative and postoperative values of the mean ejection fraction and mean PAP of patients was respectively 45.28 ± 9.67 (25-65), 46.03 ±12.4 (20-65) (p = 0.447), 36.67 ± 6.81 (30-60) mmHg, 37.81 ± 10.07 (20-70) mmHg (p = 0.378). The late mortality of cases was 5.79%. In our study, during 33.9 ± 17 (9-100) months follow up period, life expectancy was calculated as 94.7 months.

CONCLUSION

Preoperative evaluation of these patients for appropriate medical treatment at peroperative and postoperative period, coronary bypass can be performed with low morbidity and mortality rates. In the late period after surgical revascularization PH showed no significant change and had no adverse effect on quality of life.

Reversible left ventricular diastolic dysfunction on Doppler tissue imaging predicts a more favorable prognosis in chronic heart failure

BACKGROUND

Early (e')/late (a') diastolic mitral annular velocity ratio is a powerful independent predictor of poor prognosis in patients with left ventricular (LV) dysfunction. Doppler tissue imaging, however, may change over time according to intervention and medical treatment. The aim of the present study was to prospectively evaluate whether, in clinically stable patients with chronic heart failure (CHF), the decrease of an initially high e'/a' ratio on long-term therapy predicts a more favorable outcome.

METHODS AND RESULTS

One hundred and eighty-one adult patients with CHF and high e'/a' ratio (≥ 0.74) underwent repeat echocardiography 6 months after the initial examination, and were then followed up for a mean period of 20 months. After 6 months, e'/a' ratio did not change in 95 patients, whereas it was significantly decreased (<0.74) in the remaining 86 patients. During follow-up, 55 participants (30%) had cardiac events. According to multivariate Cox regression analysis, decrease in e'/a' ratio, initial New York Heart Association class III or IV, and change in LV mass index as well as in systolic mitral annular velocities emerged as independent predictors of survival.

CONCLUSIONS

The decrease of an initially high e'/a' ratio on long-term therapy predicts a more favorable outcome in clinically stable patients with CHF.

Off-Pump Coronary Artery Bypass Surgery in Severe Left Ventricular Dysfunction

Our aim was to examine hospital outcomes of coronary artery bypass surgery in patients with and without left ventricular dysfunction, with regard to the surgical technique (off- or on-pump). Between March 2007 and March 2008, 689 consecutive patients underwent isolated first-time coronary artery bypass; 127 had ejection fractions ≤30% (group 1) and 562 had ejection fractions >30% (group 2). Data of preoperative risk profiles and hospital outcomes were collected prospectively. Off-pump operations were performed in 49 (38.6%) patients in group 1 and 196 (34.9%) in group 2. The incidences of infectious, neurologic, and cardiac complications postoperatively were significantly higher in group 1. In multivariate analysis, preoperative ejection fraction ≤30% was found to be an independent risk factor for postoperative complications and hospital mortality. The subgroup of patients undergoing off-pump surgery in both groups had a significantly lower rate of total complications than those undergoing conventional on-pump operations, but no significant difference in mortality was observed between those undergoing off-pump or conventional surgery in either group. Off-pump surgery helped to limit the increased morbidity rate after coronary bypass in patients with ventricular dysfunction.

Surgical treatment of coronary multivessel disease

Coronary artery bypass grafting has had a significant impact on the treatment of angina, and has been the 'gold standard' since 1969. Its use and efficacy has been increased by revascularization in cardiac arrest and the use of the internal mammary artery. In parallel, catheter techniques have evolved by means of balloon dilatation and additional stenting. This has effected the referral to surgery despite the development of new arterialization techniques and minimally invasive surgery. As competing techniques, an acceptable equilibrium between surgery and stenting will be found within the next years.

Coronary Artery Bypass Grafting in Patients with Severe Left Ventricular Dysfunction-Early and Mid-Term Outcomes

BACKGROUND

The prevalence of patients with severe left ventricular dysfunction (LVD) referred for coronary artery bypass grafting (CABG) is increasing. The aim of the present study was to assess the outcomes of patients with severe LVD undergoing CABG.

METHODS

Outcomes of 115 consecutive patients with severe LVD (left ventricular ejection fraction [LVEF]</= 30%, mean 22 +/- 6%) undergoing isolated CABG between 1995 and 2000 were compared to 2335 patients with LVEF >30% (HEF). To further evaluate the LVD patients, they were divided into three subgroups base on LVEF: 0% to 10%, 11% to 20%, and 21% to 30%. Data were collected prospectively and entered into the departmental database of the Society of Thoracic Surgeons.

RESULTS

Patients in the LVD group had increased incidence of diabetes, chronic obstructive pulmonary disease (COPD), peripheral vascular disease, prior myocardial infarction (MI), congestive heart failure, and less elective procedures compared to the HEF group. Despite this greater risk profile, operative mortality (LVD 2.6% vs. HEF 1.2%, p = 0.19), the incidence of stroke (2.6% vs. 1.0%, p = 0.13), and perioperative MI (0.9% vs. 0.7%) were not statistically different between the groups. The incidence of respiratory (14.8% vs. 1.9%, p < 0.001), renal (5.2% vs. 1.0%, p < 0.001), and vascular (5.2% vs. 0.5%, p < 0.001) complications was significantly higher in the LVD group, resulting in a longer hospital length of stay (8 +/- 8 vs. 6 +/- 4 days, p < 0.0001). In a multivariate analysis, advanced age was as an independent predictor of hospital mortality. Average follow-up in 108 (94%) LVD patients was 36 +/- 22 months (range 2 to 78 months). Twenty-one patients expired during the follow-up, for nine the causes were cardiac-related. Three- and 5-year survival rates were 91 +/- 3% and 76 +/- 6%, respectively. Independent predictors of mid-term mortality in the LVD group by a multivariate analysis included female gender, renal failure, respiratory complications, and grade I/II mitral regurgitation (MR). At the time of follow-up, 72% of LVD patients were in functional class I/II. There were no statistically significant differences in short- and mid-term outcomes among the LVD subgroups.

CONCLUSION

CABG in patients with severe LVD can be performed with a low mortality, albeit with higher morbidity and longer length of hospital stay, than patients with LVEF >30%. Low ejection fraction per se was not a predictor of hospital mortality. CABG should be considered a safe and effective therapy for low ejection fraction patients with ischemic heart disease. Mitral valve repair/replacement in the presence of moderate degree of MR should be considered at the time of the initial operation.

Clinical decision-making and myocardial viability: current perspectives

Not all myocardium involved in a myocardial infarction is dead or irreversibly damaged. The balance between the amount of scar and live tissue, and the nature of the live tissue, determine the likelihood that contractile function will improve after revascularisation. This improvement (which defines viability) may be predicted with about 80% accuracy using several techniques. This review examines the determinants of functional recovery and how they may be integrated in making decisions regarding revascularisation.

Long-term outcome after coronary artery bypass grafting in patients with severe left ventricular dysfunction

BACKGROUND

The aim of this study was to define the potential for long-term survival with severe left ventricular dysfunction after coronary bypass and to quantify any improvement in overall functional status.

METHODS

Left ventricular dysfunction was confirmed preoperatively and the long-term survival and functional outcome after bypass was determined by follow-up studies obtained during the span of a decade.

RESULTS

From 1/1990 to 12/1999, 86 patients with severe left ventricular dysfunction (mean ejection fraction, 0.18 +/- 0.03; range, 0.10 to 0.20) underwent coronary artery bypass grafting. There were 10 perioperative deaths (11% mortality). The mean survival was 55 months (standard deviation +/- 34 months; range, 2 to 141 months) with an actual 5-year survival rate of 59% (actuarial 5-year 65%, 10-year 33%). Echocardiography obtained between 1 and 6 months, 6 months and 1 year, 1 and 2 years, 2 and 4 years, 4 and 6 years, and 6 and 11 years showed the ejection fraction improved to 0.29 +/- 0.08 (p < 0.001), 0.31 +/- 0.14 (p < 0.002), 0.35 +/- 0.08 (p < 0.001), 0.27 +/- 0.10 (p = 0.002), 0.36 +/- 0.14 (p = 0.004), and 0.30 +/- 0.11 (p = 0.004), respectively. At 1 to 6 months, 6 months to 1 year, and 1 to 2 years, the diastolic left ventricular dimension was unchanged, but the systolic left ventricular dimension decreased significantly from 5.02 +/- 0.77 cm to 4.26 +/- 0.91 cm (p = 0.046), 3.98 +/- 1.43 cm (p = 0.08), and 4.10 +/- 1.14 cm (p = 0.07). The preoperative New York Heart Association classification for all patients improved from 2.8 +/- 0.8 to 1.6 +/- 0.7 (p < 0.001) after a mean of 53 months (standard deviation +/- 34 months).

CONCLUSIONS

Patients with severe left ventricular dysfunction can derive long-term benefit from coronary bypass through improved left ventricular contractility as documented by a significantly decreased systolic left ventricular dimension and increased ejection fraction. Successful bypass is associated with a 59% actual 5-year survival rate and significantly improved New York Heart Association functional class.

Passive constraint and new shape-change devices for heart failure

Lessons learned from ventricular remodeling procedures have shown that Laplace mechanics, whereby mural tension is related to ventricular diameter, may be beneficially applied to the left ventricle (LV). Recently developed devices, predicated on the Law of Laplace, are directed at interrupting the heart-failure cascade without removing functioning myocardium. The Acorn cardiac support device is a polyester-mesh jacket placed snugly around the heart to provide end-diastolic support and prevent LV dilation. The Myosplint device uses transmural tension members to bisect the dilated LV to create a bilobed LV with decreased mural tension in each cavity. Preclinical and early clinical data with both devices appears promising and may offer a new surgical alternative for patients with worsening heart failure.