Uberto Bortolotti

Clinical outcome in patients with 19-mm and 21-mm St. Jude aortic prostheses: comparison at long-term follow-up.

BACKGROUND Small-sized prostheses for aortic valve replacement may result in residual left ventricular outflow tract obstruction. Aim of the study was to verify whether implantation of 19-mm versus 21-mm St. Jude Medical standard prostheses (St. Jude Medical, Inc, St. Paul, MN) influences long-term clinical outcome. METHODS Two hundred twenty-nine patients who underwent aortic valve replacement with 19 mm (group 1, 53 patients) or 21-mm St. Jude Medical standard prostheses (group 2, 176 patients) were included in the study. Mean follow-up of current survivors was 10+/-4 years. RESULTS Operative mortality was 7.5% in group 1 and 8.5% in group 2. At discharge, an important patient-prosthesis mismatch (effective orifice area index < or = 0.60 cm2/m2) was present in 18% of group 1 versus 5% in group 2 (p = 0.004). Among patients with body surface area less than 1.70 m2, such mismatch was present in 15% of group 1 versus 2% of group 2 (p = 0.008). At last follow-up New York Heart Association (NYHA) functional class (p < 0.001), left ventricular mass reduction (p = 0.02), mean (p = 0.002) and peak transprosthetic gradients (p < 0.001), and effective orifice area index (p = 0.005) were significantly better in group 2. Freedom from sudden death (92%+/-5% vs 99%+/-1%, p = 0.01), valve-related death (84%+/-6% vs 90%+/-5%, p = 0.02), and cardiac events (56%+/-13% vs 86%+/-4%, p = 0.008), were significantly lower in group 1. Effective orifice area index was an independent predictor of late cardiac events. CONCLUSIONS Although long-term results after aortic valve replacement with small-sized St. Jude Medical standard prostheses are satisfactory, 19-mm valve recipients show a high prevalence of important patient-prosthesis mismatch with less evident functional improvement and higher rate of cardiac events, suggesting a very cautious use of this prosthesis.

Early Results of Transmyocardial Revascularization With a Holmium Laser

BACKGROUND Transmyocardial laser revascularization (TMLR), a surgical technique designed to improve perfusion in the ischemic myocardium by creating transmural channels, has been performed thus far using a carbon dioxide laser, with apparently gratifying early results. We have investigated clinically TMLR using a holmium laser as sole therapy for patients with coronary artery disease that is not amenable to traditional treatment such as coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. METHODS From November 1995 to December 1996, 16 patients underwent TMLR using a holmium laser. Their mean age was 68 +/- 6 years and 75% were men. Previous coronary artery bypass grafting or percutaneous transluminal coronary angioplasty had been performed in 81% and 31% of the patients, respectively. Before operation, their mean anginal class was 3.4 +/- 0.5 and their mean left ventricular ejection fraction was 0.49 +/- 0.06. Six patients had unstable angina. RESULTS There were no operative deaths. The mean duration of TMLR was 27 +/- 13 minutes and the mean duration of the entire operation was 120 +/- 40 minutes. There were no major postoperative complications and the mean hospital stay was 8 +/- 4 days. There were 2 late deaths, 1 that occurred 40 days after TMLR as a result of stroke and 1 that occurred 4 months after TMLR as a result of myocardial infarction. Current survivors have been followed up for a mean of 10 +/- 4 months (range, 3 to 15 months), with 7 patients followed up for 1 year. At last follow-up, the mean anginal class had decreased to 1.8 +/- 0.7 (p = 0.001) and the patients had increased exercise tolerance and a reduced number of hospitalizations. However, no statistically significant changes in the percentage of segments with fixed or reversible ischemia and no statistically significant differences in the viability scores of lased and nonlased segments were observed. CONCLUSIONS Transmyocardial laser revascularization using a holmium laser is a simple technique with low operative risk and low morbidity. Early results confirm that clinical improvement is obtained in most patients, although significant changes in myocardial perfusion are not evident in the short term.

Histological survey of the saphenous vein before its use as autologous aortocoronary bypass graft.

A histological examination has been carried out on the saphenous veins used in 150 consecutive patients undergoing aortocoronary bypass. Morphological changes were observed frequently and consisted mainly of fibrosis of the intima and of the medial longitudinal muscular layer. Intimal fibrosis was rarely severe enough to narrow the lumen significantly. Statistical analysis disclosed that the fibrosis of the intima and the medial longitudinal muscular layer do not increase with age. The use of frozen histological sections of the saphenous vein in patients undergoing aortocoronary bypass operations could be considered in order to discard unsuitable grafts and to direct the surgeon to alternative conduits.

Valve-related complications in elderly patients with biological and mechanical aortic valves

BACKGROUND Controversy still exists about the choice of aortic prosthesis in elderly patients. This study investigates valve- and anticoagulant-related morbidity and mortality in elderly patients after aortic valve replacement (AVR) with a biologic (BP) or mechanical prosthesis (MP). METHODS Between 1981 and 1995, 355 consecutive patients aged 70 years or older (mean, 74+/-4 years; range, 70 to 87 years) underwent isolated AVR. There were 222 (63%) replacements with an MP and 133 (37%) with a BP. Mean follow-up was 3.7+/-2.8 years (range, 3 months to 15 years), with a total follow-up of 1,214 patient-years. RESULTS Hospital mortality was 7.6% (27 of 355), decreasing to 4.6% in the last 3 years. There were 55 late deaths, 33 in patients with MP and 22 in those with BP. At 10 years there was no significant difference between MP and BP recipients in the actuarial estimates of survival (51%+/-8% versus 33%+/-13%), freedom from valve-related death (82%+/-7% versus 72%+/-12%), and freedom from thromboembolism (84%+/-7% versus 94%+/-3%). In contrast, 10-year freedom from anticoagulant-related hemorrhages was 74%+/-8% for MP and 99%+/-1% for BP (p = 0.02). Only 1 structural deterioration occurred, in a patient with BP. CONCLUSIONS Satisfactory early results can be obtained in elderly patients after AVR with both MP and BP. The comparable low late survival in the two groups was predominantly influenced by non-valve-related deaths. A higher incidence of anticoagulant-related hemorrhages limits the use of MP in elderly patients. Thus, in this population, BP should be preferred not just on the basis of their expected longer durability, but mainly to avoid the risk of anticoagulant-related hemorrhages.

Anatomical study of truncus arteriousus communis with embryological and surgical considerations.

Twelve specimens of truncus arteriosus communis have been studied anatomically, with special reference to the conal anatomy and to the associated cardiac anomalies which can create additional problems if surgical repair is planned. A wide spectrum of conal morphology has been observed, suggesting that differential conal absorption is a developmental characteristic of truncus arteriousus as well as of transposition complexes. The invariable absence of septation of the ventricular infundibula and semilunar valves, in spite of the variable anatomy of the free wall of the conus, indicates that all types of truncus arteriosus, ontogenetically, should be considered as a single undivided conotruncus. Various types of ventircular septal defect were found: (a) ventricular septal defect with absent crista, in which no remnants of conal septum are present; (b) supracristal ventricular septal defect, in which vestigial conal septum is seen in front of the membranous septum; (c) bulloventricular foramen, associated with univentricular origin of the truncus from the right ventricle. Frequent associated anomalies are underdevelopment of the aortic arch, truncal valve malformations, and obstructive ventricular septal defect. The AV conduction system studied in one case showed an arrangement similar to Fallots tetralogy with the His bundle and the left bundle-branch in a safe position behind the posteroinferior rim of the defect. The postoperative fate of the frequently abnormal truncal valve and the theoretical indications for total repair for Type IV truncus are also discussed.

Mitral Valve Repair With Artificial Chordae: A Review of Its History, Technical Details, Long-Term Results, and Pathology

Mitral valve repair is considered the procedure of choice for correcting mitral regurgitation in myxomatous disease, providing long-term results that are superior to those with valve replacement. The use of artificial chordae to replace elongated or ruptured chordae responsible for mitral valve prolapse and severe mitral regurgitation has been the subject of extensive experimental work to define feasibility, reproducibility, and effectiveness of this procedure. Artificial chordae made of autologous or xenograft pericardium have been replaced by chordae made of expanded polytetrafluoroethylene (PTFE), a material with the unique property of becoming covered by host fibrosa and endothelium. The use of artificial chordae made of PTFE has been validated clinically over the past 2 decades and has been an increasing component of the surgical armamentarium for mitral valve repair. This article reviews the history, details of the relevant surgical techniques, long-term results, and fate of artificial chordae in mitral reconstructive surgery.

Pulmonary atresia with ventricular septal defect. Further anatomical observations.

An anatomnical study was undertaken of 25 hearts with pulmonary atresia and ventricular septal defect, giving special attention to the morphology of the pulmonary outflow tract and the nature of the arterial supply to the lungs. A common feature of all hearts studied was the presence of sixth aortic arch derivatives within the pericardial cavity. Eighteen specimens presented with pulmonary atresia with ventricular septal defect in situs solitus, with atrioventricular concordance and normally related great arteries, that is with the pulmonary artery remnant anterior and to the left of the aorta. A blind or atretic pulmonary infundibulum

Hemodynamic performance of stented and stentless aortic bioprostheses.

BACKGROUND This study compares the hemodynamic performance of stented and stentless bioprostheses used for aortic valve replacement in patients with aortic stenosis and small aortic root. METHODS Between 1995 and 1998, 37 patients with a 21-mm aortic annulus (group 1) underwent aortic valve replacement with either a 21-mm Edwards Perimount or a 23-mm St. Jude Toronto bioprosthesis whereas 47 patients with a 23-mm aortic annulus (group 2) received either a 23-mm Medtronic Mosaic or a 25-mm Edwards Prima bioprosthesis. In each group mean and peak gradients, effective orifice area index, and left ventricular mass index were compared during follow-up. RESULTS Group 1 patients showed a significant reduction of mean (p < 0.001) and peak gradients (p = 0.001) during follow-up, more evident for St. Jude Toronto versus Edwards Perimount (p = 0.02 and p = 0.05, respectively). Group 2 patients showed a significant reduction of mean and peak gradients (p < 0.001), more evident for Edwards Prima versus Medtronic Mosaic (p < 0.001 and p = 0.07, respectively). Effective orifice area index significantly increased only in group 1 (p = 0.005). Left ventricular mass index significantly decreased in all patients regardless of the type of valve (p < 0.001). Patients with Edwards Prima showed a trend to a higher regression of left ventricular mass index versus Medtronic Mosaic recipients (p = 0.07). CONCLUSIONS After aortic valve replacement, stented and stentless bioprostheses exhibited similar results with a more evident hemodynamic improvement during follow-up in the stentless valves. Stented bioprostheses of new generation, however, may parallel the hemodynamic performance of stentless valves and appear to be a valid alternative for aortic valve replacement in elderly patients with a small aortic annulus.

Aortic Valve Replacement With the Medtronic Mosaic Bioprosthesis: A 13-Year Follow-Up

BACKGROUND This study evaluated the long-term clinical performance of the Mosaic bioprosthesis (Medtronic Inc, Minneapolis, MN) after aortic valve replacement. METHODS From 1995 to 2008, 178 patients (48 women; mean age, 74±6 years) had aortic valve replacement. Mean functional class was 2.3±0.5, and 157 patients (88%) were in sinus rhythm. Prosthetic sizes were 23 mm in 98 patients and 25 mm in 66. Follow-up was completed in December 2009 with a cumulative duration of 1,015 patient/years (mean, 5.7±3.5 years, maximum, 13.7 years). RESULTS Early mortality was 4%, none being valve-related; of 38 late deaths 7 were valve-related. Actuarial survival at 13 years was 48%±8%. Mean functional class of current survivors was 1.2±0.6. Six embolic episodes occurred and four cases of endocarditis, with respective actuarial freedom of 92%±5% for embolism and 97%±2% for endocarditis at 13 years. Four patients required reoperations for endocarditis and 2 for structural deterioration. Actuarial freedom from structural deterioration and from reoperation for all causes was 89%±7% and 86%±7% at 13 years, with an actuarial freedom from prosthesis-related deaths of 86%±5%. Results of echocardiographic evaluation at 1 year were mean peak gradient, 20±6 mm Hg and mean effective orifice area index, 1.07±0.21 cm2/m2 for size 23 mm and 22±6 mm Hg and 1.11±0.26 cm2/m2 for size 25 mm; at 10 years, mean peak gradient and mean effective orifice area index were 28±13 mm Hg and 1.01±0.19 cm2/m2 for size 23 mm and 26±8 mm Hg and 1.08±0.18 cm2/m2 for size 25 mm. CONCLUSIONS The Mosaic bioprosthesis showed good overall performance, with low incidence of structural valve deterioration and hemodynamic stability in the long-term. Expected increased durability of this device should be verified at longer follow-up intervals.

Symptomatic improvement after transmyocardial laser revascularization: how long does it last?

BACKGROUND The aim of this study was to determine whether short-term clinical improvement after isolated transmyocardial holmium laser revascularization (TMLR) in patients with coronary artery disease not amenable to traditional treatment is maintained through a longer follow-up. METHODS Between November 1995 and June 1999 34 patients underwent TMLR (mean age, 67+/-7 years); previous revascularization procedures had been performed in 76%. Preoperatively, mean angina class was 3.6+/-0.5 in 12 patients with unstable angina; mean left ventricular ejection fraction was 47%+/-9%. RESULTS There was 1 early death due to low cardiac output. Mean duration of TMLR and of the entire operation was 25+/-12 minutes and 125+/-43 minutes, respectively. There were no major postoperative complications; mean hospital stay was 8+/-4 days. There were 8 late deaths caused by stroke (2 patients), cardiac failure (1 patient), and myocardial infarction (5 patients). Follow-up of current survivors ranges from 4 to 48 months (mean, 32+/-12 months). At 1-year follow-up mean angina class was 1.8+/-0.8; but at a later follow-up (mean, 35+/-10 months) it significantly increased to 2.2+/-0.7 (p = 0.005). Three-year actuarial survival was 76%+/-8% and freedom from cardiac events 44%+/-10%. CONCLUSIONS Our results show that after initial clinical improvement many patients experience return of angina or cardiac events; this questions the long-term symptomatic benefit of TMLR.