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Francesco Maisano

Publications and source records attributed to Francesco Maisano.

At least 19 recordsLinked to original sources
PubMed2005

Mitral valve repair for functional mitral regurgitation in end-stage dilated cardiomyopathy: role of the "edge-to-edge" technique.

BACKGROUND: The aim of this study was to assess the results of mitral valve (MV) repair in functional mitral regurgitation because of end-stage dilated cardiomyopathy (DCM). METHODS AND RESULTS: Seventy-seven patients with end-stage idiopathic (26 patients) or ischemic (51 patients) DCM underwent MV repair for functional mitral regurgitation (3 to 4+/4+). Fifty-eight patients (75.3%) were in New York Heart Association class III, and 19 (24.6%) were in IV. In 23 patients (29.8%) with a coaptation depth <1 cm, an isolated undersized annuloplasty was used. In the remaining 54 (70.1%), with a coaptation depth > or =1 cm, the "edge-to-edge" technique was associated with the annuloplasty. In most of the cases (88.3%), a complete rigid/semirigid ring was used. Concomitant coronary artery bypass graft was performed in 39 patients (50.6%). Hospital mortality was 3.8% (3 of 77). Actuarial survival was 90.7+/-3.64%, and freedom from cardiac events was 81.8+/-7.96% at 2.7 years. At a mean follow-up of 18.4+/-9.8 months (range, 1 month to 5 years) New York Heart Association class improved from 3.4+/-0.4 to 1.4+/-0.6 (P<0.0001). Mitral repair failure (recurrence of MR > or =3+/4+) was documented in 7 patients (9%): 2 in the edge-to-edge (2 of 54, 3.7%) and 5 in the isolated annuloplasty group (5 of 23, 21.7%) (P=0.03). Freedom from repair failure at 1.5 years was 95.0+/-3.4% and 77+/-12.1%, respectively (P=0.04). The absence of the edge-to-edge was the only predictor of repair failure (P=0.03). When residual MR was absent or mild, a reverse left ventricular remodeling was clearly documented. CONCLUSIONS: In patients with end-stage DCM, MV repair is feasible with low hospital mortality and important symptomatic improvement. The association of the edge-to-edge technique to the undersized annuloplasty can significantly improve the durability of the repair.

Adult↗
PubMed2005

Circulating leptin correlates with left ventricular mass in morbid (grade III) obesity before and after weight loss induced by bariatric surgery: a potential role for leptin in mediating human left ventricular hypertrophy.

CONTEXT: Obesity is frequently associated with left ventricular hypertrophy, even when uncomplicated by hypertension or diabetes mellitus. Left ventricular hypertrophy is an important risk factor for congestive heart failure. OBJECTIVE: The objective of this study was to evaluate the relationship between leptin and left ventricular mass in uncomplicated, morbid (grade 3) obesity and the existence of leptin receptors and intracellular signaling proteins in the human heart. DESIGN: Left ventricular mass (LVM) was calculated through electrocardiogram reading in normotensive grade III obese patients (World Health Organization classification) undergoing bariatric surgery [laparoscopic adjustable gastric banding (LAGB)] at baseline and 1 yr later. The control group was composed of healthy lean normotensive subjects. Leptin receptors were detected by PCR and immunocytochemistry in human heart biopsies. SETTING: This study was performed at university hospitals. PATIENTS: Thirty-one grade 3 obese patients and 30 healthy nonobese normotensive, age- and sex-matched control subjects were studied. INTERVENTION: Obese subjects underwent LAGB to induce weight loss and were evaluated at baseline and after 1 yr. RESULTS: LVM, plasma leptin, glucose, insulin levels, and homeostasis model assessment index were higher in obese than in lean controls (P < 0.01); at univariate regression analysis, LVM correlated with body mass index, leptin, and homeostasis model assessment index; at multiple regression analysis, LVM only correlated with leptin levels (P = 0.001). Obese subjects were reevaluated 1 yr after LAGB, when their body mass index changed from 46.2 +/- 1.24 to 36.6 +/- 1.05 kg/m(2) (P < 0.01); the decrease in LVM correlated only with the decrease in leptin levels (P < 0.01). We demonstrated that long and short isoforms of the leptin receptor and intracellular proteins mediating leptin signaling were expressed in human heart by RT-PCR, immunocytochemistry, or both methods. CONCLUSIONS: These data suggest that leptin could contribute to the left ventricular hypertrophy in humans.

Adult↗
PubMed2005

An annular prosthesis for the treatment of functional mitral regurgitation: finite element model analysis of a dog bone-shaped ring prosthesis.

BACKGROUND: Undersized annuloplasty is commonly used in the treatment of functional mitral regurgitation. However, in the case of severely dilated ventricles, annuloplasty may be inadequate to counteract leaflet tethering. My colleagues and I hypothesized that modifying the shape of the annular prosthesis to account for the specific anatomy of functional mitral regurgitation could challenge extreme leaflet tethering. METHODS: Using finite element model simulations, we tested valve competence after the implantation of conventional D-shaped versus dog bone-shaped annuloplasty rings, the latter of which was designed to selectively reduce the septolateral dimension of the annulus. Three models were compared: model A, simulating the native mitral valve; model B, simulating the same valve after annuloplasty with a conventional D-shaped annuloplasty; and model C, simulating a dog-bone annuloplasty ring implantation. Each model was then challenged by progressively pulling the tip of the papillary muscles away from the annulus plane to simulate ventricular remodeling and leaflet tethering. Valve competence was compared in each model for each degree of leaflet tethering. RESULTS: After maximal leaflet tethering simulation (4-mm apical displacement of the papillary tips), the regurgitant area increase was 70.4 mm2 for model A and 52.9 mm2 for model B. In model C, the regurgitant area was only negligibly affected by papillary displacement, increasing to 3.9 mm2. CONCLUSIONS: An annular prosthesis with selective reduction in the septolateral dimension is more effective than a conventional prosthesis for treating leaflet tethering in functional mitral regurgitation. Use of disease-specific annular prostheses is needed to improve the results of valve reconstruction.

Animals↗
PubMed2005

Beat-to-beat effects of intraaortic balloon pump timing on left ventricular performance in patients with low ejection fraction.

BACKGROUND: Intraaortic balloon counterpulsation (IABP) timing errors during arrhythmia may result in afterload increases which may negatively influence left ventricular (LV) ejection and LV mechanical dyssynchrony. The aim of our study was to determine beat-to-beat effects of properly timed IABP, premature IAB inflation, and late IAB deflation on LV performance and LV mechanical dyssynchrony in heart failure patients undergoing cardiac surgery. METHODS: In 15 patients, LV pressure-volume relations and LV dyssynchrony were measured by conductance volume catheter. Properly timed IABP was evaluated at a 1:1 assist ratio within a 10 seconds time-span. Premature IAB inflation and late IAB deflation were evaluated at a 1:4 assist ratio. RESULTS: Properly timed 1:1 IABP acutely decreased LV end-systolic volume by 6.1% (p < 0.0001) and LV end-systolic pressure by 17.5% (p < 0.0001) due to decreased aortic impedance. Stroke volume (SV) increased by 14% (p < 0.0001), which correlated markedly with a decrease of LV mechanical dyssynchrony (p < 0.0001). The largest SV increases occurred in patients with lowest contractile state. Premature IAB inflation decreased SV by 20% (p < 0.0001) due to abrupt increase of LV afterload during late ejection. Late IAB deflation increased SV and stroke work by 18% (p < 0.0001) and 16% (p < 0.01) respectively, due to increased afterload during early ejection and decreased afterload during late ejection. CONCLUSIONS: Left ventricular performance during IABP is causally related to changes in LV afterload, and the timing of these changes in relation to contraction or relaxation phases, to LV mechanical dyssynchrony and to contractile state.

Humans↗
PubMed2005

Automatic intraaortic balloon pump timing using an intrabeat dicrotic notch prediction algorithm.

PURPOSE: The efficacy of intraaortic balloon counterpulsation (IABP) during arrhythmic episodes is questionable. A novel algorithm for intrabeat prediction of the dicrotic notch was used for real time IABP inflation timing control. DESCRIPTION: A windkessel model algorithm was used to calculate real-time aortic flow from aortic pressure. The dicrotic notch was predicted using a percentage of calculated peak flow. Automatic inflation timing was set at intrabeat predicted dicrotic notch and was combined with automatic IAB deflation. EVALUATION: Prophylactic IABP was applied in 27 patients with low ejection fraction (< 35%) undergoing cardiac surgery. Analysis of IABP at a 1:4 ratio revealed that IAB inflation occurred at a mean of 0.6 +/- 5 ms from the dicrotic notch. In all patients accurate automatic timing at a 1:1 assist ratio was performed. Seventeen patients had episodes of severe arrhythmia, the novel IABP inflation algorithm accurately assisted 318 of 320 arrhythmic beats at a 1:1 ratio. CONCLUSIONS: The novel real-time intrabeat IABP inflation timing algorithm performed accurately in all patients during both regular rhythms and severe arrhythmia, allowing fully automatic intrabeat IABP timing.

Aged↗
PubMed2005

Acute decrease of left ventricular mechanical dyssynchrony and improvement of contractile state and energy efficiency after left ventricular restoration.

OBJECTIVE: Surgical left ventricular restoration by means of endoventricular patch aneurysmectomy in patients with postinfarction aneurysm should result in acute improved left ventricular performance by decreasing mechanical dyssynchrony and increasing energy efficiency. METHODS: Nine patients with left ventricular postinfarction aneurysm were studied intraoperatively before and after ventricular restoration with a conductance volume catheter to analyze pressure-volume relationships, energy efficiency, and mechanical dyssynchrony. The end-systolic elastance was used as a load-independent index of contractile state. Left ventricular energy efficiency was calculated from stroke work and total pressure-volume area. Segmental volume changes perpendicular to the long axis were used to calculate mechanical dyssynchrony. Statistical analysis was performed with the paired t test and least-squares linear regression. RESULTS: Endoventricular patch aneurysmectomy reduced end-diastolic volume by 37% (P < .001), with unchanged stroke volume. Systolic function improved, as derived from increased +dP/dt(max), by 42% (P < .03), peak ejection rate by 28% (P < .02), and ejection fraction by 16% (P < .0002). Early diastolic function improved, as shown by reduction of -dP/dt(max) by 34% (P < .006) and shortened tau by 30% (P < .001). Left ventricular end-systolic elastance increased from 1.2 +/- 0.6 to 2.2 +/- 1 mm Hg/mL (P < .001). Left ventricular energy efficiency increased by 36% (P < .002). Left ventricular mechanical dyssynchrony decreased during systole by 33% (P < .001) and during diastole by 20% (P < .005). CONCLUSIONS: Left ventricular restoration induced acute improvements in contractile state, energy efficiency, and relaxation, together with a decrease in left ventricular mechanical dyssynchrony.

Aged↗
PubMed2005

[Severe aortic stenosis successfully treated with percutaneous aortic valve implantation].

Patients with severe calcific aortic stenosis are occasionally not amenable to surgery because of advanced age or severe co-morbidities. Percutaneous aortic valve dilation is used but has only limited time relief. While preclinical evidence on percutaneous aortic valve replacement seems promising, only very limited clinical data are available worldwide. We hereby present the first case of percutaneous aortic valve replacement successfully performed in Italy in a 74-year-old high-risk female. This case emphasizes the technical challenges inherent to this procedure and its promising role in selected very high-risk patients with severe aortic stenosis, notwithstanding the early and long-term risk of adverse events.

Aged↗
PubMed2004

A method to avoid annular downsizing during knot tying.

Pericardial annuloplasty has been used as an alternative to prosthetic annuloplasty. One drawback of pericardial annuloplasty is the risk of cinching of tissues during knot tying, possibly leading to uncontrolled downsizing and to complications such as mitral stenosis and systolic anterior motion of the anterior leaflet. A simple modification of the sequence of knot tying is described to avoid this complication.

Aged↗
PubMed2004

A novel technique for correction of severe tricuspid valve regurgitation due to complex lesions.

OBJECTIVES: Correction of tricuspid regurgitation due to complex lesions (not treatable with annuloplasty only) is associated with suboptimal results. To improve the efficacy of valve repair in this context, we developed a new surgical approach, which consists of stitching together the central part of the free edges of the leaflets producing a 'clover' shaped valve. Our preliminary experience with this novel technique is reported. METHODS: Between 2001 and 2003, 14 patients (mean age 57+/-17 years), with severe tricuspid regurgitation due to complex lesions, underwent valve repair with this novel approach in combination with annuloplasty. The aetiology of the disease was post-traumatic in five cases, degenerative in eight and secondary to dilated cardiomyopathy in one. Anterior leaflet prolapse/flail was present in most patients associated with posterior and/or septal leaflet prolapse or tethering. Annular and right ventricular dilatation was present in all cases. Mitral valve repair/replacement was concomitantly performed in nine patients. RESULTS: Hospital mortality was 7.1% (1/14). At follow-up extending to 22 months (mean 12+/-6.3), all survivors were asymptomatic. At the last echocardiogram tricuspid regurgitation was absent or mild in 13 patients and moderate in one. Mean tricuspid valve area and gradient were 4.2+/-0.4 cm(2) and 2.7+/-1.4 mmHg, respectively. CONCLUSIONS: Despite the short follow-up, this novel technique appears to be an easy, rapid and effective approach to correct severe tricuspid regurgitation due to complex lesions. Such a repair restored tricuspid valve competence, even in the presence of huge RV dilatation and pulmonary hypertension.

Adult↗
PubMed2004

Echocardiographic classification of chronic ischemic mitral regurgitation caused by restricted motion according to tethering pattern.

Although the mechanism of ischemic mitral regurgitation (MR) is understood, the echocardiographic picture of ischemic MR is not homogeneous. Ninety-two consecutive patients with chronic ischemic MR due to restricted motion were divided into two groups according to tethering pattern: the asymmetric group with predominant posterior tethering of both leaflets (54 patients) and the symmetric one with predominant apical tethering of both leaflets (38 patients). The mitral deformation indexes, LV global (volume, function and sphericity) and local (papillary muscle displacements and regional wall motion score index) remodeling were evaluated. All indexes of global LV remodeling were significantly higher in the symmetric than asymmetric group (all p < 0.0001), such as the posterior and lateral displacement of the anterior papillary muscle (both p < 0.04), the papillary muscle separation and the anterior papillary muscle wall motion index (both p < 0.0001). The origin as well as the direction of the jet was central in all patients of the symmetric group. In the asymmetric one the origin was central in 78% of the cases and arising from the medial commissure in 22% whereas the jet direction was posterior and central in 83% and 17% of patients, respectively. Therefore, it is possible to distinguish at least two subgroups of patients with ischemic MR due to restricted motion on the basis of tethering pattern, different degree of local and global LV remodeling and characteristics of the regurgitant jet.

Aged↗
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↗