Carlo Bassano

REGRESSION OF LEFT VENTRICULAR HYPERTROPHY AFTER AORTIC VALVE REPLACEMENT FOR AORTIC STENOSIS WITH DIFFERENT VALVE SUBSTITUTES

OBJECTIVE Stentless biologic aortic valves are less obstructive than stented biologic or mechanical valves. Their superior hemodynamic performances are expected to reflect in better regression of left ventricular hypertrophy. We compared the regression of left ventricular hypertrophy in 3 groups of patients undergoing aortic valve replacement for severe aortic stenosis. Group I (10 patients) received stentless biologic aortic valves, group II (10 patients) received stented biologic aortic valves, and group III (10 patients) received bileaflet mechanical aortic valves. METHODS Echocardiographic evaluations were performed before the operation and after 1 year, and the results were compared with those of a control group. Left ventricular diameters and function, left ventricular wall thickness, and left ventricular mass were assessed by echocardiography. RESULTS Group I patients had a significantly lower maximum and mean transprosthetic gradient than the other valve groups (P = .001). One year after operation there was a significant reduction in left ventricular mass for all patient groups (P < .01), but mass did not reach normal values (P = .05). Although the rate of regression in the interventricular septum and posterior wall thickness differed slightly among groups, their values at follow-up were comparable and still higher than control values (P = .002). The ratio between interventricular septum and posterior wall and the ratio between wall thickness and chamber radius did not change significantly at follow-up. CONCLUSIONS Because the number of patients was relatively small, we could not use left ventricular mass regression after I year to distinguish among patients undergoing aortic valve replacement for aortic stenosis by means of valve prostheses with different hemodynamic performances.

Long-Term Outcome of Coronary Artery Bypass Grafting in Patients With Left Ventricular Dysfunction

BACKGROUND Coronary artery bypass grafting (CABG) is a well-accepted therapeutic strategy for patients with multivessel coronary artery disease and left ventricular dysfunction. The aim of the study was to evaluate long-term results after CABG in patients with preoperative left ventricular ejection fraction (LVEF) of 0.35 or less. METHODS Data from 302 consecutive patients (mean age, 62 +/- 8.7 years) with LVEF of 0.35 or less who had undergone CABG were analyzed. Epinephrine and enoximone with or without norepinephrine were used to increase cardiac index. Intra-aortic balloon pump or left ventricular assist devices, or both, were used in case of postoperative low output syndrome. RESULTS Complete revascularization was achieved in 298 of 302 patients (98.7%); internal thoracic artery was used in 294 (97.4%). Operative mortality was 5.3%; independent predictors of operative mortality were emergency CABG (p = 0.005), history of ventricular arrhythmias (p = 0.007), and previous anterior myocardial infarction (p = 0.05). At follow-up, all-cause mortality was 30.8%, and 10-year survival was 63% +/- 4%; independent predictors of late all-cause mortality were history of ventricular arrhythmias (p < 0.0001), chronic renal dysfunction (p = 0.0004), and diabetes mellitus (p = 0.04). Cardiac death was 20.4%, and 10-year freedom from cardiac death was 73% +/- 3.3%; independent predictors of cardiac death were history of ventricular arrhythmias (p = 0.004), chronic renal dysfunction (p = 0.03), and more than one previous anterior myocardial infarction (p = 0.004). At 80 +/- 44 months of follow-up, echocardiography showed significant LVEF improvement (0.43 +/- 0.09 versus 0.28 +/- 0.06, p < 0.0001). Ten-year freedom from myocardial infarction was 87% +/- 3%. CONCLUSIONS Excellent long-term results after CABG can be expected for patients with LVEF of 0.35 or less. Complete revascularization and internal thoracic artery grafting are associated with high freedom from myocardial infarction. Careful treatment of arrhythmias, diabetes, and renal dysfunction is necessary to improve long-term survival.

Extent and pattern of regression of left ventricular hypertrophy in patients with small size carbomedics aortic valves

OBJECTIVE To assess the extent and pattern of regression of left ventricular hypertrophy after valve replacement for aortic stenosis, we studied 26 patients receiving either 19 or 21 mm CarboMedics valves (group I, 13 patients) or either 23 or 25 mm CarboMedics valves (group II, 13 patients). The studies were done before the operation and after 3 years, and results were compared with those of 10 control patients. METHODS Left ventricular end-diastolic and end-systolic diameters and volumes, ejection fraction and fractional shortening, and interventricular septum and posterior wall thickness were measured. The ratio between interventricular septum and posterior wall thickness, the ratio between left ventricular wall thickness and left ventricular chamber radius, and the left ventricular mass were then calculated. RESULTS At follow-up there was a significant reduction in the left ventricular mass, interventricular septum, and posterior wall thickness for both patient groups (p < 0.01). However, only the posterior wall thickness reached normal values; the interventricular septum and the left ventricular mass indices were still significantly greater than in the control group (p < 0.01). Because of the incomplete regression of interventricular septal hypertrophy, the ratio between interventricular septum and posterior wall thickness was similar between both patient groups but it was significantly higher than in control subjects (p < 0.01). The ratio between wall thickness and chamber radius did not decrease significantly in group II patients, in whom it remained above the control values. CONCLUSION Having a bileaflet aortic prosthesis of one size larger did not seem to significantly influence the pattern and the extent of regression of left ventricular hypertrophy after an intermediate period of follow-up.

Mid-term follow-up of aortic root remodelling compared to Bentall operation

OBJECTIVES Aortic valve sparing with root remodelling has proven useful in cases of aortic regurgitation secondary to ascending aorta disease. An excessive rate of re-operation for recurrent aortic regurgitation after this conservative approach might compensate the prosthesis-related risk of the Bentall operation. METHODS From January 1995 to September 2000, 69 consecutive patients with aortic expansive aneurysm and concomitant aortic valve disease, were submitted to the Bentall operation (group A, n=37) in the presence of an abnormal valve, or to root remodelling (group B, n=32) in cases of secondary aortic incompetence. One patient in group A and four in group B had Marfan syndrome. The follow-up was 1021 patient-months (range, 1-68 months) in group A and 926 in group B (1-64 months). The event-free survival was calculated using the Kaplan-Meier method, and the difference between curves was evaluated using the Mantel-Cox log-rank test. RESULTS The operative mortality was 5% in group A and 0% in group B. One patient died at follow-up in group A and none in group B. Four patients (three Marfan) in group B were re-operated on because of recurrent aortic regurgitation. The 5-year event-free survival was 88+/-7% in group A and 82+/-8% in group B (P=0.58). Early residual aortic regurgitation remained stable over time only in patients with good early results. CONCLUSIONS Mid-term follow-up failed to reveal statistically significant differences in the clinical outcome between remodelling and the Bentall operation. Our results support the widespread use of root remodelling, provided that an indication to this conservative approach is achieved after careful, case-by-case evaluation. A good early operative result is likely to remain stable over time.

Residual aortic valve regurgitation after aortic root remodeling without a direct annuloplasty

BACKGROUND Aortic insufficiency secondary to degenerative aneurysms of the ascending aorta can be surgically treated with replacement of the valve or with remodeling of the aortic root. METHODS In 15 patients who underwent aortic root remodeling from January 1994 to December 1996, we evaluated the postoperative aortic regurgitation and correlated it with several anatomic and functional variables. Operative success was defined as a residual aortic regurgitation less than or equal to 1 on a scale of 0 to 4. RESULTS Root dimensions and aortic incompetence decreased significantly after the operation (p < 0.0001). The difference between preoperative and postoperative root diameters (p = 0.0006) and the presence of Marfans syndrome (p < 0.0001) were independently predictive of persisting significant aortic insufficiency. Operative success was obtained in patients with a difference between preoperative and postoperative root diameters smaller than 30 mm. CONCLUSIONS Aortic root remodeling is effective in reducing aortic regurgitation. Severe aortic root dilatation may result in excessive geometric alteration, leading to suboptimal results. The choice of a larger graft contributes to avoiding excessive geometric constraint of a profoundly diseased aortic root. Indication to undergo root remodeling should be evaluated cautiously in patients with Marfans syndrome.

Levels of Troponin I and Cardiac Enzymes After Reinfusion of Shed Blood in Coronary Operations

BACKGROUND Reinfusion of shed blood after coronary artery bypass grafting might increase the levels of cardiac enzymes with consequent difficulties in the diagnosis of perioperative myocardial infarction. METHODS Thirty consecutive patients undergoing coronary artery bypass grafting who bled at least 400 mL within the first 4 hours after operation underwent reinfusion of shed blood. Thirty consecutive patients who were not autotransfused served as control. All patients underwent enzyme determination (total creatine kinase, MB fraction, lactate dehydrogenase, and troponin I) in the shed blood and in circulating blood preoperatively, at arrival in the intensive care unit, and 6, 24, and 48 hours after operation. RESULTS The shed blood contained significantly higher concentration of cardiac enzymes than the circulating blood at all time intervals (p = 0.0001). The levels of creatine kinase, its MB fraction, and lactate dehydrogenase in circulating blood were significantly elevated in patients receiving autotransfusion up to 24 hours after autotransfusion. The blood levels of troponin I were not significantly different between the two group of patients at all time points. The percent fraction of MB did not increase after autotransfusion. CONCLUSIONS The measurement of cardiac troponin I is a useful marker for the diagnosis of perioperative myocardial infarction in patients undergoing transfusion of shed blood after coronary operation.

Survival and Durability of Mitral Valve Repair Surgery for Degenerative Mitral Valve Disease

Abstract  Aim of the study: To evaluate the results after standardized techniques of mitral valve repair (MVr) for treatment of degenerative mitral regurgitation (MR) and to analyze risk factors for late outcomes. Methods: Two hundred and sixty‐one patients (mean age 63 ± 12 years) underwent MVr between January 1999 and January 2010 for degenerative MR. In the last five years, all repair techniques were performed routinely using annuloplasty prosthetic ring, with or without quadrangular or triangular resection of posterior leaflet and/or edge‐to‐edge technique as always indicated by intraoperative transesophageal echocardiography. Mean follow‐up (99% complete) was 54 ± 38 (range, 6 to 137) months. Results: Operative mortality was 0.8% (2/261), 10‐year actuarial survival 89%± 3%. At 10 years of follow‐up freedom from cardiac death was 94%± 2.6%, from reoperation 95%± 2.4%, from thromboembolism 96%± 2.1%, and from endocarditis 100%. Independent predictor of late all‐causes mortality was advanced age at operation (71 ± 10 years vs. 62 ± 12 years, p = 0.0068). Late progression to moderate or severe MR was observed in 12/256 patients (4.7%). Independent predictor of late progression to moderate or severe MR was annuloplasty without the use of prosthetic ring (p = 0.04). Reoperation was required in six patients (2.3%). Follow‐up echocardiography showed improvement of MR, left ventricular end‐diastolic and end‐systolic diameters, left atrial diameter, and systolic pulmonary artery pressure (p < 0.0001 for all comparisons with preoperative values). Conclusions: MVr is a low‐risk, durable surgical procedure. Standardized techniques, with the routine use of prosthetic ring, improve late results. (J Card Surg 2011;26:360‐366)

Five‐Year Clinical Outcome and Patency Rate of Device‐Dependent Venous Grafts After Clampless OPCAB with PAS‐Port Automated Proximal Anastomosis: The PAPA Study

To evaluate long‐term clinical performance and angiographic patency of automated proximal venous anastomoses following clampless coronary artery bypass (C‐CAB).

The fate at mid-term follow-up of the on-pump vs. off-pump coronary artery bypass grafting surgery

Aims To evaluate the fate of on-pump coronary artery bypass grafting (ON-pump CABG) vs. off-pump coronary artery bypass grafting (OP-CABG) surgery at mid-term follow-up. Methods From January 2008 to December 2010, 369 patients underwent surgical myocardial revascularization by means of OP-CABG techniques (n = 166) or with ON-pump CABG (n = 203). Data of the two groups of patients were retrospectively analyzed. Results As compared with OP-CABG, in the ON-pump CABG patients, mean value of Logistic EuroSCORE (8.1 ± 7.8% vs. 6.2 ± 5.9%, P = 0.04), more extended coronary disease (2.7 ± 0.5 vs. 2.5 ± 0.7 diseased vessels/patient, P < 0.001) consequently requiring greater number of grafts/patient (2.9 ± 0.9 vs. 2.3 ± 0.9, P < 0.0001), and emergency surgery (12 vs. 6%, P = 0.03) were more frequently observed. Operative mortality was 1.9% in ON-pump CABG vs. 1.2% in OP-CABG (P = 0.6) and incidence of stroke 2.46 vs. 1.81% (P = 0.7). The incidence of stroke was reduced at 1.2% when OP-CABG PAS-Port ‘clamp-less’ technique was used. Intraoperatively, costs per patient were higher for OP-CABG vs. ON-pump CABG (1.930,00 +1.050,00 &OV0556;, if PAS-port system was included, vs. 1.060,00 &OV0556; for ON-pump surgery). ICU stay (1.9 ± 1.0 days vs. 1.4 ± 0.7 days) and total postoperative in-hospital stay (5.3 ± 3.3 days vs. 5.5 ± 3.5 days) were similar in both groups. At 4 years, survival (91 ± 13% in the ON-pump CABG vs. 84 ± 19% in the OP-CABG), freedom from major adverse cardiac events (composite end-point of all-cause death, myocardial infarction, and repeat coronary revascularization of the target lesion) (82 ± 9% vs. 76 ± 14%), and major adverse cardiac and cerebrovascular events (80 ± 11% vs. 72 ± 16%) were not significantly different. Freedom from late cardiac death was slightly significant higher after ON-pump CABG (98 ± 4% vs. 90 ± 10%, P = 0.05). Conclusion Mid-term freedom from composite end-points is similar after ON-pump CABG and OP-CABG. Freedom from cardiac death appears to be better after ON-pump CABG. OP-CABG needs for more expensive surgical technique. OP-CABG performed by an experienced surgical team using ‘clamp-less’ techniques can be an effective strategy in reducing postoperative stroke.

Bicuspid aortic root spared during ascending aorta surgery: an update of long-term results

BACKGROUND Bicuspid aortic valve (BAV) aortopathy is well known in literature even if only few data exist regarding isolated supra-coronary aneurysm with normally functioning valve and root. Aim of this study is to clarify the long-term fate of bicuspid aortic root spared at the time of ascending aorta surgery. METHODS We identified forty-seven patients (mean age, 57±11 y; range, 35-81 y, 31 males) who were treated by means of supracoronary aortic replacement in presence of normally functioning BAV and not significantly enlarged sinues of Valsalva. Clinical follow-up (mean 93±50 months; range, 21-207) was 98.9% complete. RESULTS Freedom from cardiac death at 5- and 10-year was 95%±5% and 83%±16%. Three surviving patients required reoperation for the development of aortic insufficiency [2 cases treated by aortic valve replacement (AVR)] or for progression of aortic stenosis (AS) [1 case treated by transcatheter aortic valve implantation (TAVI)]. Freedom from new procedure on aortic valve was 100% and 94.4%±5.6% at 5- and 10-year. Composite event-free survival at 5- and 9-year was 82%±18% and 69%±30%. CONCLUSIONS Although in the setting of a BAV, aortic root integrity seems to remain stable during long term follow up with low rate of reoperation and occurrence of new adverse event.