Relation of aneurysmectomy in patients with advanced left ventricular remodeling to postoperative left ventricular filling pressure, redilatation with ischemic mitral regurgitation

Nomogram Predicts Improvement of Ischemic Mitral Regurgitation after Coronary Artery Bypass Grafting

BACKGROUND

Developing a nomogram to predict improvement in moderate ischemic mitral regurgitation (IMR) after coronary artery bypass grafting (CABG) is in need.

METHODS

Between 2010 and 2018, data were retrospectively collected from 112 patients with prior myocardial infarction and moderate IMR undergoing CABG. Patients were divided into two groups based on IMR degree 1 year after CABG as follows: Improved Group with no or mild IMR (n=54) and Failure Group with moderate or severe IMR (n=58). To determine the predictors of postoperative IMR improvement, preoperative clinical and echocardiographic data were compared, and a nomogram was formulated based on all independent predictors. Discriminative ability, calibration, and clinical usefulness of the prediction model were assessed.

RESULTS

Independent predictors of IMR improvement after CABG constructing the nomogram included duration between infarction and operation, poster-inferior to left ventricular volume ratio, maximum difference of the time to reach minimum systolic volume of 16 segments, P3 leaflet tethering angle, and annular Non-planar angle. The nomogram exhibited well-fitted calibration curves and excellent discriminative ability. The area under receiver operating characteristic curve was 0.974. Patients with a score > 236 demonstrated a high probability of IMR improvement (sensitivity, 90.7%; specificity, 93.1%). Patients in the Improved Group demonstrated greater actuarial survival rates than those in the Failure Group.

CONCLUSIONS

The nomogram combining 5 preoperative clinical and echocardiographic predictors provides an accurate preoperative estimation of moderate IMR improvement after surgery, with excellent discriminative ability. Based on this nomogram, patients with a higher score predict higher probabilities of IMR improvement.

Left ventricular regional dyssynchrony predicts improvements in moderate ischaemic mitral regurgitation after off-pump coronary artery bypass

OBJECTIVES

The aim of this study was to explore the predictors of the improvement in moderate ischaemic mitral regurgitation (IMR) after off-pump coronary artery bypass grafting (OPCAB) focusing on left ventricular (LV) dyssynchrony.

METHODS

A prospective study was performed among 135 patients (age at surgery, mean ± SD: 67.0 ± 8.2 years, 33.3% women) with prior myocardial infarction and moderate IMR undergoing OPCAB from 2008 to 2015. Preoperative and follow-up clinical and echocardiographic parameters were analysed, focusing on LV global/regional dyssynchrony. Patients were grouped by IMR at 1 year postoperatively: improved group with no or mild IMR (n = 61) and failure group with moderate or severe IMR (n = 67). Data were compared between groups to explore the predictors of IMR improvement after OPCAB.

RESULTS

Seven patients who died before the 1-year postoperative assessment were excluded. At the 1-year follow up, there were 61 patients in the improved group and 67 patients in the failure group. Preoperatively, the improved group had smaller LV global dyssynchrony, LV regional dyssynchrony (papillary muscle systolic dyssynchrony; improved group versus failure group: 48.5 ± 4.5 ms vs 57.1 ± 3.9 ms; P < 0.001) and greater LV ejection fraction (improved group versus failure group: 44.7 ± 5.0% vs 36.7 ± 6.7%; P < 0.001) than the failure group. Papillary muscle systolic dyssynchrony (odds ratio 1.556, 95% confidence interval 1.313-1.845; P < 0.001) and preoperative ejection fraction (odds ratio 0.799, 95% confidence interval 0.691-0.924; P = 0.002) were independent predictors of moderate IMR improvement after OPCAB.

CONCLUSIONS

In the selected patients, preoperative moderate IMR could be relieved by coronary artery bypass grafting. Greater ejection fraction and absence of LV regional dyssynchrony may predict the improvement in moderate IMR after coronary artery bypass grafting, suggesting that LV dyssynchrony especially regional dyssynchrony and preserved ventricular function would be important to the outcome of patients with moderate IMR.

Resizable ventricular patch plasty in the porcine left ventricle: a pilot study

OBJECTIVE

: Endoventricular circular patch plasty is a method used to reconstruct the ventricular cavity in patients with (post) ischemic left ventricular aneurysm or global dilatation. However, late redilatation with mitral regurgitation has been reported, in which postoperative apex shape seems to play an important role. We studied the feasibility of ventricular volume downsizing with a variably shaped patch in porcine hearts.

METHODS

: In five in vitro and two acute animal experiments, a dyskinetic aneurysm was simulated with a pericardial insert. Reducing patch surface by changing patch shape diminished end-diastolic volume. In vitro, static end-diastolic volume was determined for each patch shape using volumetry and echocardiography. In the acute animal experiments, preliminary observations of patch behavior in live material were made, and pressure/time relationship, dPdTmax, was registered.

RESULTS

: In vitro, bringing the convex patch into a flat plane reduced LV volume from 66 ± 7 mL (aneurysm) to 49 ± 5 mL. Four of 5 patch shapes further reduced volume to a mean of 38 ± 7 mL (P = 0.03). The in vitro echocardiographic measurements correlated with volumetry findings (r = 0.81). In the acute animal experiments, dPdTmax varied with patch shape, independent of volume changes.

CONCLUSIONS

: In this pilot study, in vitro shape configuration of the resizable ventricular patch resulted in a calibrated end-diastolic volume reduction. The data of the two in vivo pilot experiments clearly indicate that change in patch configuration in the situation of more or less unchanged end-diastolic volume had impact on cardiac performance. Future studies must substantiate the results of this observation.

Transient late-onset ischemic mitral regurgitation following Dor's procedure

A 60-year-old man developed anteroseptal acute myocardial infarction with subsequent left hemiplegia. Echocardiography detected apical aneurysm with thrombus. Coronary artery bypass grafting with Dor's procedure were performed. Chronic heart failure (CHF) developed three months after the surgery. CHF with mitral regurgitation (MR) continued for more than two months and then disappeared. When surgical intervention is considered for late MR after Dor's procedure, it is important to consider that late-onset MR after Dor's procedure can be transient with full medication, which may require four or more months to achieve its full effects.

Beneficial Hemodynamic and Clinical Effects of Surgical Ventricular Restoration in Patients With Ischemic Dilated Cardiomyopathy

BACKGROUND

Surgical ventricular restoration is increasingly applied in patients with ischemic dilated cardiomyopathy. Previous studies show promising results with regard to survival and clinical outcome. However, a comprehensive midterm analysis of this approach on left ventricular (LV) and right ventricular function is not yet available. We investigated biventricular function and clinical status at 6-month follow-up.

METHODS

We investigated the effects of surgical ventricular restoration on clinical variables, LV volume, right ventricular reverse remodeling, LV dyssynchrony, tricuspid regurgitation, and pulmonary artery pressure in 21 patients with ischemic dilated cardiomyopathy (New York Heart Association class III or IV) who underwent surgical ventricular restoration and coronary artery bypass grafting. Additional surgery included mitral annuloplasty (n = 14) and tricuspid valve annuloplasty (n = 8). Clinical variables (New York Heart Association class, quality-of-life questionnaire, 6-minute hall-walk test) and echocardiographic variables were assessed at baseline and at 6 months.

RESULTS

At 6-month follow-up, all clinical variables were significantly improved. Left ventricular ejection fraction improved from 0.27 +/- 0.10 to 0.36 +/- 0.11 (p < 0.01), LV end-diastolic volume decreased from 248 +/- 78 mL to 152 +/- 50 mL (p < 0.001), and LV end-systolic volume decreased from 186 +/- 77 mL to 101 +/- 50 mL (p < 0.001). Left ventricular dyssynchrony decreased from 61 +/- 41 ms to 12 +/- 12 ms (p < 0.001). Right ventricular annular diameter decreased from 30 +/- 7 mm to 27 +/- 6 mm, right ventricular short-axis from 30 +/- 9 mm to 27 +/- 7 mm, and right ventricular long-axis from 90 +/- 7 mm to 79 +/- 10 mm (all p < 0.05). Finally, significant reductions in severity of tricuspid regurgitation (from 1.3 +/- 1.1 to 0.9 +/- 0.6; p = 0.001) and pulmonary artery pressure (42 +/- 11 mm Hg to 28 +/- 10 mm Hg; p = 0.015) were observed.

CONCLUSIONS

Surgical ventricular restoration resulted in improvement of clinical variables, significant LV volume reduction, and reduced LV dyssynchrony at 6-month follow-up. In addition, right ventricular reverse remodeling was noted with reductions in tricuspid regurgitation and pulmonary artery pressure.