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Francesco Maisano

Publications and source records attributed to Francesco Maisano.

34 records · Page 2Linked to original sources
PubMed2004

Haemodynamics and mechanics following partial left ventriculectomy: a computer modeling analysis.

Mechanics following partial left ventriculectomy is still poorly understood. A computational cylindrical model of the left ventricle was developed, based on the myocardial fibre behaviour for the evaluation of the mechanical and haemodynamical effects of the operation. A healthy left ventricle with physiological geometry and function and a dilated hypokinetic heart were investigated. Haemodynamic and mechanical data were obtained at baseline and compared with those obtained at different degrees of volume reduction. Data included: ejection fraction (EF); stroke volume (SV); end-systolic and end-diastolic pressure-volume relationships (ESPVR and EDPVR), and efficiency. EF increases following volume reduction in both simulation but, concurrently, SV shows modest improvement (dilated ventricle) or reduction (healthy ventricle) at progressive degrees of resection. The ESPVR and EDPVR slope increases and shifts leftward with the resection extent, but the increase of the ESPVR slope is more pronounced in dilated ventricle. Efficiency is improved in the dilated heart after resections, while does not improve when the healthy-heart volume is reduced. The simulation of partial left ventriculectomy suggests an improvement of systolic performance, counterbalanced by increased diastolic stiffness following inverse remodelling. Efficiency of simulated dilated ventricles is enhanced by volume reduction, suggesting a favourable effect of reduction of the metabolic demand of the failing heart.

Animals↗
PubMed2004

"Edge-to-edge" repair for anterior mitral leaflet prolapse.

The aim of this study is to report our results in a series of 150 consecutive patients (mean age 53 +/- 15.4 years) in whom mitral regurgitation (MR) due to isolated anterior mitral leaflet (AML) prolapse was corrected using the edge-to-edge (E to E) technique over a period of more than 10 years. At admission, 49 (32.6%) patients were in NYHA class I, 46 (30.6%) in II, 51 (34%) in III and 4 (2.6%) in IV. In the great majority of the cases (111 patients, 74%), degenerative disease was the cause of MR. Hospital mortality was 0.6% (1/150). There were 7 late deaths. The actuarial overall survival and freedom from reoperation at 9 years were 91.6% +/- 3.16% and 96.6% +/- 1.74%, respectively. At follow-up (4.5 +/- 3.21 years, range 2 months-12 years), the mean mitral valve area was 2.7 +/- 0.5 cm(2) and mitral regurgitation was absent or mild in 132 patients (88%). The results of this study demonstrate the effectiveness and durability of the E to E repair in the setting of AML prolapse. In our institution, this technique, in conjunction with annuloplasty, remains the method of choice to correct segmental prolapse of the AML.

Adolescent↗
PubMed2004

Surgical options in ischemic cardiomyopathy.

The prevalence of ischemic dilated cardiomyopathy in western countries is increasing despite improvements in prevention, diagnosis, and treatment of cardiovascular disease. The management of patients with coronary artery disease and severe left ventricular dysfunction continues to be challenging and the mortality rate with medical therapy alone in this setting remains very high. Since heart transplantation represents a realistic option just for a very small number of patients, in recent years a variety of classic surgical interventions have been improved or optimized to address the complex and multifactorial pathophysiology of the ischemic heart failure picture. Myocardial revascularization, left ventricular restoration, mitral valve repair, passive containment device implantation, and surgical ablation of atrial fibrillation represent some of the "conventional" procedures which are currently in use or under development for the surgical treatment of ischemic cardiomyopathy. For several of them, the exact indications and results are not yet established and significant changes and improvements should reasonably be waited over the next few years. As techniques are refined and more data become available, the optimum surgical strategy for patients with advanced ischemic heart failure is likely to become clearer and more effective.

Atrial Fibrillation↗
PubMed2004

[Off-pump endovascular treatment of aortic arch aneurysms].

BACKGROUND: Traditional repair of aortic arch aneurysms requires cardiopulmonary bypass, hypothermia and circulatory arrest. Endovascular repair is an attractive, less invasive alternative that may change our therapeutic approach. The aim of this study was to review our clinical experience with endovascular treatment of aortic arch aneurysms and to address the new problems in this area. METHODS: In the last 5 years, we treated 21 patients for aortic arch pathology with an "off-pump" endovascular repair (18 men, 3 women, mean age 71.4 +/- 7.2 years). We used 26 stent grafts (5 Gore Excluder TAG, 3 Endomed Endofit, 6 Medtronic Talent, 12 Cook Zenith TX1) with a mean of 1.2 graft/patient. Proximal fixation of endograft was achieved by means of aortic "de-branching" in 11 cases. In 10 cases the left subclavian artery was intentionally covered without revascularization. Follow-up included clinical examination, chest X-ray and computed tomography at discharge and at 6-month intervals thereafter. RESULTS: Technical success was 85% (18/21). There was one in-hospital death (4.7%) due to endograft migration. We observed 2 cases of type I endoleak (9.5%). One surgical conversion was performed 2 weeks after the procedure, because of total collapse of the stent graft with rupture of three stents. No complications related to the coverage of the left subclavian artery were observed. At a mean follow-up of 18.7 +/- 12.8 months, no mortality or morbidity including new-onset endoleak, stent-graft migration and thrombosis of supra-aortic grafts were recorded. CONCLUSIONS: Endovascular treatment of aortic arch pathology is feasible even in elderly patients. However, accurate placement in the arch and aneurysm sealing with the currently available devices, may be challenging due to the involvement of supra-aortic vessels, the anatomical curvature of the arch, the high blood flow, and substantial movement of the aorta with each heartbeat.

Aged↗
PubMed2004

Percutaneous mitral valve repair procedures.

Percutaneous mitral valve procedures are under investigation as a novel method to treat mitral valve insufficiency with a catheter-based, closed heart, non-surgical approach. The technical opportunities, the expectations for the future and the implications for the conventional surgery are discussed.

Cardiac Catheterization↗
PubMed2003

Surgical methods to reverse left ventricular remodeling in congestive heart failure.

In this review article, we describe the most common surgical procedures currently used to reverse or arrest remodeling of the left ventricle in patients with congestive heart failure (CHF). The selection of the appropriate operation in a patient is a complex decision-making process, rigorously based on pathophysiologic considerations. In this population, all factors affecting the surgical risk should be carefully evaluated preoperatively, and surgery should be recommended when definite benefits in survival and quality of life can be reasonably predicted. Quite often, patients with CHF require a combination of different procedures to address all the pathophysiologic components determining the clinical picture. In particular, in this review we describe the surgical restoration of the left ventricle, the isolated coronary artery bypass graft procedure, the correction of mitral regurgitation, diastolic support (from dynamic cardiomyoplasty to passive containment), and mechanical assist devices. Moreover, in the future, the role of surgery in the treatment of CHF will be strongly modified by the advent of gene therapy, cell therapy, and engineered artificial myocardial tissue.

Cardiac Surgical Procedures↗
PubMed2003

Detection of mechanisms of immediate failure by transesophageal echocardiography in quadrangular resection mitral valve repair technique for severe mitral regurgitation.

Residual mitral regurgitation (MR) after repair is a risk factor for late reoperation. The use of intraoperative transesophageal echocardiography (IOTEE) decreases the incidence of immediate repair failure. This study identifies the mechanisms of immediate failure by IOTEE in the quadrangular resection technique, a well-standardized mitral valve repair procedure to guide further repair procedures. Two hundred five consecutive patients underwent quadrangular resection due to prolapse or flail posterior leaflet. Twenty-four patients (11%) had immediate failure. Immediate reinstitution of cardiopulmonary bypass ("second pump run") was needed in 21 patients (10%) for further repair. The identified mechanisms of failure were residual cleft provoking interscallop malcoaptation into the posterior leaflet in 8 patients, residual prolapse of the anterior or posterior leaflets in 1 and 4 patients, respectively, residual annular dilation in 3, left ventricular outflow obstruction in 2, suture dehiscence in 2, and other mechanisms in another 2 patients. In 20 patients (95%), IOTEE guided further repair with resolution of the residual MR, whereas 1 patient underwent valve replacement due to pharmacologically untreatable left ventricular outflow obstruction. In conclusion, even if this type of valve repair technique is well standardized, the incidence of immediate failure is not negligible. IOTEE identified the mechanisms of the immediate failure and guided further repair procedures, thus reducing the incidence of valve replacement (0.5%) without increasing perioperative mortality and morbility.

Adult↗
PubMed2003

Midterm results of edge-to-edge mitral valve repair without annuloplasty.

OBJECTIVE: Edge-to-edge mitral valve repair is usually performed in association with annuloplasty, with rare exceptions. We retrospectively analyzed the results of ringless edge-to-edge repair, particularly in view of minimally invasive and percutaneous approaches. METHODS: From November 1993 to December 2001, 81 patients underwent edge-to-edge mitral repair without associated annuloplasty. The cause was degenerative in most patients. In 32 patients the annulus was severely calcified. Type I lesions were present in 6 patients, type II lesions in 60 patients, and type III lesions in 15 patients. A double-orifice repair was done in 69 patients, and paracommissural repair was done in 12 patients. In 5 patients edge-to-edge repair was used as a rescue procedure. RESULTS: There were 3 hospital and 4 late deaths, for a 4-year survival of 85% +/- 6.7%. At latest follow-up, 63 patients were in New York Heart Association classes I or II, and 9 patients were in classes III or IV. Nine patients required reoperation (89% +/- 3.9% overall freedom from reoperation at 4 years). Annular calcification was associated with a greater reoperation rate (77% +/- 22% vs 95% +/- 4.6% freedom from reoperation, P =.03). Intraoperative water testing and postrepair transesophageal echocardiography predicted late failure. Only 1 of 42 patients required reoperation in the follow-up period when annular calcification, rheumatic disease, or rescue procedure were not present as risk factors. CONCLUSIONS: Our data confirm overall suboptimal results of the edge-to-edge technique when annuloplasty is not added to the repair. Annular calcification, rheumatic cause, and edge-to-edge repair done as a rescue procedure were associated with the worst outcome. Midterm results in selected patients encourage future developments in catheter-based edge-to-edge procedures.

Calcinosis↗
PubMed2003

Multiplane transesophageal echocardiography performed according to the guidelines of the American Society of Echocardiography in patients with mitral valve prolapse, flail, and endocarditis: diagnostic accuracy in the identification of mitral regurgitant defects by correlation with surgical findings.

Multiplane transesophageal echocardiography is a useful tool to study mitral regurgitation. We evaluated the diagnostic accuracy of multiplane transesophageal echocardiography performed according to the guidelines of the American Society of Echocardiography. We used 4 midesophageal and 2 transgastric views in 313 patients with degenerative lesions, endocarditic lesions, or both to identify regurgitant defects, comparing transesophageal echocardiography results with surgical findings. The overall diagnostic accuracy using individual scallops was 97.2% (P <.00001) with a sensitivity of 96.6% and a specificity of 97.6%. Considering the single sections of the mitral valve, an accuracy of 98%, 97.1%, and 98%, was found, respectively, for the lateral, middle, and medial third of the anterior leaflet. For the posterior leaflet, the accuracy was 98% for the lateral scallop, 98.4% for the middle, and 96.1% for the medial. This strategy provides good accuracy in diagnosing both simple and challenging mitral-valve lesions and its widespread use should be recommended.

Adult↗
PubMed2002

Off-pump coronary artery surgery with the use of anastomotic devices: an additional tool for the challenging patient.

BACKGROUND: Avoidance of aortic side-clamping may decrease the risk of embolization to the brain and other organs during coronary revascularization. Herein we describe our preliminary experience with an anastomotic device for proximal anastomosis construction. METHODS: From October 2000 to June 2001, 18 selected patients undergoing beating heart surgery had an aorta-to-saphenous vein graft anastomosis performed with the St. Jude Medical Aortic connector. RESULTS: All anastomoses were successfully deployed. In two patients there was a minor anastomotic bleeding and in other two cases a kinking occurred due to a too short and a too long graft respectively. One patient, with graft occlusion on the fourteenth postoperative day, underwent successful percutaneous revascularization. CONCLUSIONS: Our preliminary results indicate that the aortic anastomotic device is safe and effective and its use could be widened once long-term results are available.

Aged↗
PubMed2002

Surgical restoration of the left ventricle for postinfarction aneurysm.

BACKGROUND: Surgical left ventricular reduction is under investigation as an alternative to, or a bridge for, heart transplantation in patients with a left ventricular aneurysm. In fact, acute myocardial infarction can result in the development of a dyskinetic or akinetic left ventricular aneurysm which may in turn cause congestive heart failure, ventricular arrhythmias, and the formation of mural thrombi. The aim of this study was to evaluate the current operative risk of surgical restoration of the left ventricle and the early and late clinical results. METHODS: From January 1997 to December 2001, 94 patients (84 males and 10 females) presenting with a postinfarction aneurysm were submitted to surgical restoration of the left ventricle. All patients presented with symptoms of heart failure and/or angina. The preoperative NYHA functional class was: I in 6 patients, II in 22 patients, and III in 66 patients. No patient was in NYHA class IV at the time of surgery. The preoperative ejection fraction was 30 +/- 7.9%. In 25 patients mural thrombi were identified and surgically removed. In patients with preoperative evidence of ventricular arrhythmias the Harken procedure was performed intraoperatively. The ventricular preoperative and postoperative performances were also studied in 10 patients using P-V loops obtained through a conductance catheter. RESULTS: The in-hospital mortality was 3.2%. The mean length of hospitalization was 7 +/- 2.9 days. At follow-up (mean 26 +/- 14.8 months) we observed an early improvement in the ejection fraction (30 +/- 7.9 vs 48 +/- 8.0%) and a decrease in the end-diastolic and end-systolic volumes and mean pulmonary pressure (139 +/- 37 vs 84 +/- 17 ml/m2, 105 +/- 39 vs 52 +/- 20 ml/m2, 35 +/- 8.4 vs 23 +/- 4.3 mmHg). CONCLUSIONS: These results suggest that ventricular restoration is indicated in all patients with a postinfarction dyskinetic or akinetic aneurysm. The operation, if performed appropriately, is associated with a low in-hospital mortality and morbidity. A postoperative improvement in the early and long-term cardiac functions was demonstrated. An improvement in symptoms and quality of life was documented, increasing our expectations of an increased long-term survival.

Cardiac Surgical Procedures↗
PubMed2002

Mitral valve reserve in double-orifice technique: an exercise echocardiographic study.

BACKGROUND AND AIM OF THE STUDY: The edge-to-edge technique is used to restore valvular competence in mitral insufficiency. The efficacy of the method is under debate due to the potential for creating functional mitral stenosis. An exercise echocardiographic study was carried out to investigate valve function and hemodynamics in patients who had undergone double-orifice mitral valve repair. METHODS: Thirty patients (mean age 49.1 +/- 12.7 years) with previous double-orifice mitral valve repair underwent exercise echocardiography (10 W/min). An annular prosthesis was present in 28 patients (93%). The mean and maximum mitral valve gradient, planimetric valve area, stroke volume, systolic pulmonary artery pressure, heart rate and systolic blood pressure were measured at baseline and at peak stress. RESULTS: At peak stress, heart rate (77.7 +/- 12.2 versus 118.6 +/- 26.0 beats/min, p < 0.00001), systolic blood pressure (124.1 +/- 10.9 versus 146.6 +/- 22.8 mmHg, p < 0.00001) and stroke volume (78.0 +/- 10.2 versus 97.0 +/- 15.1 ml, p < 0.00001) were significantly increased, showing a physiological behavior of the mitral valve. The mean mitral valve gradient (2.8 +/- 1.3 versus 4.6 +/- 1.9 mmHg, p < 0.00001), maximum mitral valve gradient (6.4 +/- 2.8 versus 10.5 +/- 4.6 mmHg, p < 0.00002) and systolic pulmonary artery pressure (22.8 +/- 6.1 versus 28.2 +/- 9.9 mmHg, p < 0.001) were increased, but not to pathologic levels. Planimetric valve area increased significantly (3.2 +/- 0.6 versus 4.3 +/- 0.7 cm2, p < 0.00001). A significant negative linear correlation was found between the relative change in mitral valve area and planimetric valve area at rest (r = -0.51, p < 0.05). CONCLUSION: The double-orifice repair, even with concomitant ring annuloplasty, does not cause mitral valve obstruction, either at baseline or during physical exercise, and does not affect valve hemodynamic and valve reserve.

Adolescent↗
PubMed2002

3-D computational analysis of the stress distribution on the leaflets after edge-to-edge repair of mitral regurgitation.

BACKGROUND AND AIM OF THE STUDY: Edge-to-edge repair is an effective, recently introduced method to correct mitral insufficiency by suturing the leaflets at the site of regurgitation, though durability of the method has not been proven. To overcome the limitations of the clinical approach, simulations may be used to predict clinical outcome. In this study, the mechanical stress acting on leaflets imposed by the edge-to-edge suture was evaluated as a means of assessing the clinical risk of late fibrosis or tissue degeneration. METHODS: A 3-D finite element simulated the stress pattern following edge-to-edge repair. Valve behavior was evaluated both in systole and in diastole. Both 4-mm and 8-mm edge-to-edge sutures were simulated, as well as annular dilation. RESULTS: Systolic simulations validated the model by comparison with previous models of the mitral valve. Diastolic stresses were negligible in the native mitral valve; after edge-to-edge repair (8-mm suture), circumferential and longitudinal stress values were 308 kPa and 489 kPa, respectively, and comparable with those observed at systolic peak (449 kPa and 617 kPa, respectively). With a 4-mm suture, longitudinal stresses decreased both close to the suture (-41.5%) and in the annular region (-68%), while circumferential stresses increased (+37%) close to the suture and decreased (-27%) in the annular region. A 20% dilation of the annulus was followed by increased stresses in the annular region and close to the suture. CONCLUSION: Leaflet distortion and altered stress distribution occur on the leaflets after edge-to-edge repair. Diastolic peak stress values were comparable with those calculated in systole. The clinical implication is a doubled exposure of valve components to systolic stresses, as if the heart rate were doubled. The use of a prosthetic annuloplasty ring is favorable in the presence of annular dilation to reduce stresses acting on the leaflets after edge-to-edge repair.

Chordae Tendineae↗
PubMedDate not supplied

Performance of a real-time dicrotic notch detection and prediction algorithm in arrhythmic human aortic pressure signals.

A novel algorithm for real-time detection and prediction of the dicrotic notch from aortic pressure waves was evaluated in arrhythmic aortic pressure signals from heart failure patients. A simplified model of the arterial tree was used to calculate real-time aortic flow from aortic pressure. The dicrotic notch was detected at the first negative dip from the calculated flow, prediction of the notch was performed using a percentage of the decreasing flow. The performance of the real-time dicrotic notch detection algorithm (RTDND) was evaluated during severe arrhythmia from aortic pressure signals of 12 patients. The RTDND was able to detect the dicrotic notch in 98.1%. No false positive dicrotic notch identifications were observed. Prediction of the dicrotic notch was tested at 40%, 20%, and 0% of the decreasing calculated aortic flow. The mean time-delays to the notch were 68 +/- 14 ms, 55 +/- 12 ms, and 43 +/- 8 ms, respectively. Given these small variability, intra-beat prediction of the dicrotic notch may be used for real-time intra-aortic balloon counterpulsation inflation timing.

Aged↗
PubMedDate not supplied

Combined endovascular treatment of a descending thoracic aortic aneurysm and off-pump myocardial revascularization-a case report.

Endovascular intervention is an alternative form of treatment for patients with thoracic aortic aneurysms. Coexistent cardiovascular diseases may adversely influence the postoperative course and affect the long-term prognosis. The case of a 76-year-old man with severe coronary artery disease and a thoracic aortic aneurysm is reported. A single-stage procedure of off-pump coronary artery revascularization and endoluminal exclusion of the descending thoracic aortic aneurysm was performed. The patient was treated first with off-pump coronary artery bypass graft (left internal mammary artery on the left anterior descending coronary artery and two single venous grafts from ascending aorta to obtuse marginal artery and posterior descending artery). After heart revascularization, two Thoracic Excluder endovascular grafts (34 x 100 and 37 x 100 mm) were implanted to treat the descending thoracic aortic aneurysm. Follow-up with computed tomography angiography showed successful exclusion of the thoracic aneurysm 12 months after the procedure. The patient is well and free of symptoms 18 months later.

Aged↗