Myocardial fibrosis in asymptomatic patients undergoing surgery for mitral and aortic valve regurgitation.

BACKGROUND: Chronic heart valve regurgitation induces left ventricular (LV) volume overload, leading to the development of hypertrophy and progressive dilatation of the ventricle to maintain physiological cardiac output. In order to prevent potential irreversible LV structural changes, the identification of the best timing for treatment is pivotal. OBJECTIVE: To assess the presence and extent of fibrosis in myocardial tissue in asymptomatic patients with valvular heart disease (VHD) and preserved LV dimensions and function undergoing cardiac surgery. METHODS: Thirty-nine patients were enrolled. Sixteen patients were affected by aortic or mitral regurgitation: they were all asymptomatic, undergoing valve surgery according to VHD European Society of Cardiology guidelines. Twenty-three patients with end-stage nonischemic dilated cardiomyopathy (DCM) and severe LV dysfunction undergoing cardiac surgery for implantation of a durable left ventricular assist device (LVAD) served as controls. During surgery, VHD patients underwent three myocardial biopsies at the level of the septum, the lateral wall and LV apex, while in LVAD patients the coring of the apex of the LV was used. For both groups, the tissue samples were analyzed on one section corresponding to the apical area. All slides were stained with hematoxylin and eosin and Masson's trichrome staining and further digitalized. The degree of fibrosis was then calculated as a percentage of the total area. RESULTS: Of 39 patients, 23 met the inclusion criteria: 12 had mitral or aortic insufficiency with a preserved ejection fraction and 11 had idiopathic dilated cardiomyopathy. Quantitative analysis of apical sections revealed a myocardial fibrosis amount of 10 ±â€Š6% in VHD patients, while in LVAD patients the mean apical myocardial fibrosis rate was 38 ±â€Š9%. In VHD patients, fibrosis was also present in the lateral wall (9 ±â€Š4%) and in the septum (9 ±â€Š6%). CONCLUSION: Our case series study highlights the presence of tissue remodeling with fibrosis in asymptomatic patients with VHD and preserved LV function. According to our results, myocardial fibrosis is present at an early stage of the disease, well before developing detectable LV dysfunction and symptoms. Since the relationship between the progressive magnitude of myocardial fibrosis and potential prognostic implications are not yet defined, further studies on this topic are warranted.

Long-term results of tricuspid annuloplasty with 3-dimensional-shaped rings: effective and durable!

OBJECTIVES: 3-Dimensional (3D)-shaped rings are largely adopted for tricuspid annuloplasty, but evidence about their long-term results is scanty. The goal of this study was to analyse the long-term results of tricuspid annuloplasty with 3D-shaped rings. MATERIALS AND METHODS: A retrospective review of our prospectively maintained database was carried out to identify all patients who underwent tricuspid valve repair with 3D-shaped rings between January 2011 and December 2014. Kaplan-Meier methods were used to analyse long-term survival. Cumulative incidence function using death as the competitive outcome was used to estimate cardiac death. RESULTS: A total of 168 patients were identified. The median age was 66 years. Eighty-two patients (49%) were in advanced New York Heart Association functional class III-IV. Atrial fibrillation (AF) was present in 101 (60%); the median ejection fraction was 60%. In 82 (49%) patients, a Medtronic 3D Contour annuloplasty ring was employed; in the remaining 86 (51%) patients, an Edwards MC3 ring was used. Cumulative incidence function of cardiac death, with non-cardiac death as a competing risk, was 1.9 ± 1.1%, 95% confidence interval (CI) (0.51-4.95) at 7 years. The cumulative incidence function of recurrence of tricuspid regurgitation (TR) ≥2+ at 7 years was 14 ± 3.17%, 95% CI (8.49-20.82). Recurrence of TR ≥2+ at 7 years was not significantly different between the Medtronic 3D Contour and the Edwards MC3 rings (P = 0.3). AF was identified as the only independent predictor of recurrence of TR ≥2+. CONCLUSIONS: 3D-shaped rings are effective and durable. TR recurrence was relatively low at 7 years and usually moderate (2+/4+) without a significant difference between the 2 types of rings. The role of AF as a predictor of TR recurrence was confirmed.

Is commissural closure associated with mitral annuloplasty a durable technique for the treatment of mitral regurgitation? A long-term (≤15 years) clinical and echocardiographic study.

OBJECTIVE: Mitral regurgitation (MR) due to commissural prolapse/flail can be corrected by suturing the margins of the anterior and posterior leaflets in the commissural area (commissural closure). The long-term results of this type of repair are unknown. Our aim was to assess the clinical and echocardiographic outcomes of this technique up to 15 years after surgery. METHODS: From 1997 to 2007, 125 patients (age, 56.8 ± 15.7 years; left ventricular ejection fraction, 58.1% ± 7.1%) with MR due to pure commissural prolapse/flail of 1 or both leaflets underwent commissural closure combined with annuloplasty. The etiology of the disease was degenerative in 88.8% and endocarditis in 11.2%. The commissural region involved was posteromedial in 96 patients (76.8%) and anterolateral in 29 (23.2%). RESULTS: Hospital mortality was 1.6%. At discharge, MR was absent or mild in 120 patients (97.5%) and moderate (2+/4+) in 3 (2.4%). Clinical and echocardiographic follow-up was 98.4% complete (mean length, 7.1 ± 3.0 years; median, 6.7; longest follow-up, 15). At 11 years, the actuarial survival, freedom from cardiac death, and freedom from reoperation was 78.8% ± 6.2%, 95.2% ± 3.3%, and 97.4% ± 1.4%, respectively. At the last echocardiographic examination, MR 3+ or greater was demonstrated in 4 patients (3.3%). Freedom from MR 3+ or greater at 11 years was 96.3% ± 1.7%. No predictors for recurrence of MR 3+ or greater were identified. The mean mitral valve area and gradient was 2.9 ± 0.4 cm(2) and 3.4 ± 1.1 mm Hg, respectively. New York Heart Association class I to II was documented in all cases. CONCLUSIONS: Commissural closure repair combined with annuloplasty provides excellent clinical and echocardiographic long-term results in patients with MR due to commissural lesions.

Can the edge-to-edge technique provide durable results when used to rescue patients with suboptimal conventional mitral repair?

OBJECTIVES: The 'edge-to-edge' technique (EE) can be used as a bailout procedure in case of a suboptimal result of conventional mitral valve (MV) repair. The aim of this study was to assess the long-term outcomes of this technique used as a rescue procedure. METHODS: From 1998 to 2011, of 3861 patients submitted to conventional MV repair for pure mitral regurgitation (MR), 43 (1.1%) underwent a rescue edge-to-edge repair for significant residual MR at the intraoperative hydrodynamic test or at the intraoperative transoesophageal echocardiography. Residual MR was due to residual prolapse in 30 (69.7%) patients, systolic anterior motion in 12 (27.9%) and post-endocarditis leaflet erosion in 1 (2.3%). According to the location of the regurgitant jet, the edge-to-edge suture was performed centrally (60.5%) or in correspondence with the anterior or posterior commissure (39.5%). The original repair was left in place. RESULTS: There were no hospital deaths. Additional cross-clamp time was 15.2 ± 5.6 min. At hospital discharge, all patients showed no or mild MR and no mitral stenosis. Clinical and echocardiographic follow-up was 97.6% complete (median length 5.7 years, up to 14.6 years). At 10 years, actuarial survival was 89 ± 7.4% and freedom from cardiac death 100%. Freedom from reoperation and freedom from MR ≥ 3+ at 10 years were both 96.9 ± 2.9%. At the last echocardiogram, MR was absent or mild in 37 patients (88%), moderate in 4 (9.5%) and severe in 1 (2.4%). No predictors for recurrence of MR ≥ 2+ were identified. The mean MV area and gradient were 2.8 ± 0.6 cm(2) and 2.7 ± 0.9 mmHg. NYHA I-II was documented in all cases. CONCLUSIONS: A 'rescue' EE can be a rapid and effective option in case of suboptimal result of 'conventional' MV repair. Long-term durability of the repair is not compromised.

[Evolution in surgical repair of heart valves: implications for follow-up]. / Evoluzione delle tecniche di chirurgia riparativa delle valvole cardiache: implicazioni per il follow-up.

The number of patients undergoing surgical heart valve repair has been increasing during the last years, particularly in high-volume centers. Several factors related to poor outcomes after surgical repair have been identified in different observational studies, leading to a better preoperative patient selection and improved long-term clinical and echocardiographic follow-up.

Undersized annuloplasty for functional mitral regurgitation: is it responsible for clinically relevant mitral stenosis during exercise?

BACKGROUND AND AIM OF THE STUDY: The study aim was to assess if an undersized mitral annuloplasty for functional mitral regurgitation (FMR) in dilated cardiomyopathy can determine a clinically relevant mitral stenosis during exercise. METHODS: Both, rest and stress echocardiography were performed in 12 patients submitted to an undersized ring annuloplasty for FMR in dilated cardiomyopathy. The mean ring size was 27 +/- 1.3 mm. All patients were in NYHA functional classes I-II, were in stable sinus rhythm, and without significant residual mitral regurgitation (grade < or = 2/4). RESULTS: At peak exercise (mean 81 +/- 12 W), the main cardiac performance indices were significantly improved, including systolic blood pressure (121 +/- 5.6 versus 169 +/- 14 mmHg, p < 0.001), stroke volume (63 +/- 15 versus 77 +/- 14 ml, p < 0.001), left ventricular ejection fraction (43 +/- 9% versus 47 +/- 9%, p = 0.001), and systolic right ventricular function (pulsed tissue Doppler index peak systolic velocity: 8.6 +/- 1.7 versus 11.1 +/- 3.2 cm/s, p = 0.004). A mild increase in planimetric mitral valve area was observed at peak exercise (2.12 +/- 0.4 versus 2.17 +/- 0.3 cm2, p = 0.05). Although the transmitral mean gradient was increased from 3.2 +/- 1.2 to 6.3 +/- 2.3 mmHg (p < 0.0001), the systolic pulmonary artery pressure did not change significantly (27 +/- 2.8 versus 30.1 +/- 6.4 mmHg, p = 0.3), thus revealing a preserved cardiac adaptation to exercise. CONCLUSION: In these preliminary data, postoperative clinically relevant mitral stenosis was not observed in patients submitted to mitral repair for FMR. Stress echocardiography represents a valuable tool to assess an appropriate cardiac response to exercise and to detect a significant exercise-induced pulmonary hypertension after undersized annuloplasty ring surgery.

Mid-term results of tricuspid annuloplasty with a three-dimensional remodelling ring.

OBJECTIVE: To assess the results of tricuspid annuloplasty performed with the Edwards MC3 remodeling ring. METHODS: From 2005 to 2007, 140 patients with tricuspid regurgitation (TR) secondary to left-sided valve disease (mean age 63.8 ± 11.6, permanent pacemaker in 7.8%, LVEF 56.4 ± 10.1%, LVEDD 54.1 ± 8 mm, SPAP 52.5 ± 14.4 mmHg) underwent tricuspid annuloplasty using the MC3 ring. Dilatation of the tricuspid annulus was present in all patients. Other concomitant mechanisms of TR (moderate leaflet prolapse, pacemaker wires, leaflets' retraction) were documented in 21 cases (15%). All patients underwent concomitant left-sided valve surgery. Ring size was between 28 and 32 in 84.3% of patients. RESULTS: Hospital mortality was 3.5% and actuarial survival at 3 years 94.8 ± 2.1%. Mean follow-up of the 135 hospital survivors was 22 ± 9.5 months (median 23 months). Echocardiography at hospital discharge documented no or mild TR in 119 patients (87%), moderate TR (2+/4+) in 15 (11%) and moderate-to-severe (3+/4+) in 1 patient (0.7%). At echocardiographic follow-up moderate TR was present in 14 patients (10.3%) and moderate-to-severe TR in 2 (1.4%). At 3 years freedom from TR ≥ 2+ was 88.1 ± 2.78% and freedom from TR ≥ 3+ was 94.3 ± 4.89. Predictors of TR ≥ 2+ at hospital discharge and at follow-up were preoperative LVEF (OR:0.8; p = 0.001 at discharge; HR:0.9; p = 0.003 at follow-up) and the presence of other mechanisms of TR besides annular dilatation (OR:10.8; p = 0.007 at discharge; HR:6.1; p = 0.003 at follow-up). CONCLUSION: Tricuspid annuloplasty with the MC3 ring provides satisfactory early results which remain stable at mid-term follow-up. The presence of other mechanisms besides annular dilatation leads to residual valve insufficiency after ring annuloplasty alone.

Mitral replacement or repair for functional mitral regurgitation in dilated and ischemic cardiomyopathy: is it really the same?

BACKGROUND: This was a study to compare the results of mitral valve (MV) repair and MV replacement for the treatment of functional mitral regurgitation (MR) in advanced dilated and ischemic cardiomyopathy (DCM). METHODS: One-hundred and thirty-two patients with severe functional MR and systolic dysfunction (mean ejection fraction 0.32 ± 0.078) underwent mitral surgery in the same time frame. The decision to replace rather than repair the MV was taken when 1 or more echocardiographic predictors of repair failure were identified at the preoperative echocardiogram. Eighty-five patients (64.4%) received MV repair and 47 patients (35.6%) received MV replacement. Preoperative characteristics were comparable between the 2 groups. Only ejection fraction was significantly lower in the MV repair group (0.308 ± 0.077 vs 0.336 ± 0.076, p = 0.04). RESULTS: Hospital mortality was 2.3% for MV repair and 12.5% for MV replacement (p = 0.03). Actuarial survival at 2.5 years was 92 ± 3.2% for MV repair and 73 ± 7.9% for MV replacement (p = 0.02). At a mean follow-up of 2.3 years (median, 1.6 years), in the MV repair group LVEF significantly increased (from 0.308 ± 0.077 to 0.382 ± 0.095, p < 0.0001) and LV dimensions significantly decreased (p = 0.0001). On the other hand, in the MV replacement group LVEF did not significantly change (from 0.336 ± 0.076 to 0.31 ± 0.11, p = 0.56) and the reduction of LV dimensions was not significant. Mitral valve replacement was identified as the only predictor of hospital (odds ratio, 6; 95% confidence interval, 1.1 to 31; p = 0.03) and overall mortality (hazard ratio, 3.1; 95% confidence interval, 1.1 to 8.9; p = 0.02). CONCLUSIONS: In patients with advanced dilated and ischemic cardiomyopathy and severe functional MR, MV replacement is associated with higher in-hospital and late mortality compared with MV repair. Therefore, mitral repair should be preferred whenever possible in this clinical setting.

Long-term results of mitral repair for functional mitral regurgitation in idiopathic dilated cardiomyopathy.

OBJECTIVES: While the results of mitral repair in ischaemic mitral regurgitation have been repeatedly reported, less data are available about the outcome of surgical repair of functional mitral regurgitation (FMR) in idiopathic dilated cardiomyopathy (iDCM) which represents the topic of this study. METHODS: Fifty-four iDCM patients (mean age 63 ± 10.5 years) underwent mitral valve repair for severe FMR. Coronary angiography confirmed the absence of coronary disease in all patients. Most of the patients (77.7%) were in New York Heart Association (NYHA) class III-IV. Pre-operative ejection fraction (EF) was 30.4 ± 8.5%, left ventricle end-diastolic diameter (LVEDD) 67.5 ± 7.8 mm, left ventricle end-systolic diameter (LVESD) diameter 53.9 ± 8.3 mm. Concomitant procedures were atrial fibrillation (AF) ablation (19 patients) and tricuspid repair (17 patients). Follow-up was 100% complete (mean 4.2 ± 2.5 years, median 4.2 years, range 3.3 months-11.1 years). RESULTS: In-hospital mortality was 5.6%. Actuarial survival at 6.5 years was 69 ± 8.8%. Patients submitted to successful AF ablation and/or cardiac resynchronization therapy (CRT) had a significantly better survival (91 ± 7.9 vs 67 ± 9.5%, P = 0.01). Freedom from MR≥3+/4+ was 89.1 ± 5.7% at 6.5 years. Follow-up echocardiography showed a reduction in LVEDD (P < 0.0001) and LVESD (P = 0.0003). Mean EF increased to 38.7 ± 12.4% (P < 0.0001). Multivariate analysis identified successful ablation of AF and/or CRT (P = 0.01) and higher preoperative EF (0.03) as predictors of overall survival. Successful ablation of AF and/or CRT (P = 0.02) and lower preoperative systolic pulmonary artery pressure (0.04) were identified as independent predictors of reverse LV remodelling at follow-up. At last follow-up, 86.2% of the patients were in NYHA II or less. CONCLUSIONS: Mitral repair for FMR in well-selected iDCM patients is associated with low hospital mortality and significant clinical benefit at late follow-up. Concomitant successful AF ablation and/or CRT provide a major symptomatic and prognostic advantage and should be associated to mitral surgery whenever indicated.

The GeoForm annuloplasty ring for the surgical treatment of functional mitral regurgitation in advanced dilated cardiomyopathy.

OBJECTIVE: To assess the results of the three-dimensional (3D)-shaped GeoForm ring for the treatment of functional mitral regurgitation (FMR). METHODS: Seventy-four patients with severe FMR and systolic dysfunction underwent GeoForm ring implantation. Forty-six patients (62%) were in the New York Heart Association (NYHA) class III-IV. Concomitant procedures were coronary artery bypass grafting (CABG) (33 patients (pts)), tricuspid repair (23 pts), atrial fibrillation ablation (20 pts), aortic valve replacement (eight pts) and left-ventricular (LV) reconstruction (five pts). RESULTS: Hospital mortality was 9%. Three more patients died after hospital discharge. Overall survival was 81.1 ± 6.6% at 3.5 years. The 67 hospital survivors underwent clinical and echocardiographic follow-up at a mean follow-up period of 1.9 ± 1.25 years (median 1.7 years). MR was absent or mild in 83% of the patients (56/67), moderate in 7% (5/67), and moderate to severe in the remaining 9% (6/67). At 3.5 years, overall freedom from MR ≥ 3+ was 85.1 ± 8% and freedom from MR ≥ 2+ was 75.1 ± 8.6%. Statistical analysis identified preoperative asymmetric tethering with prevalent restricted motion of the posterior leaflet as the only predictor of recurrence of MR ≥ 2+ (hazard ratio (HR) 6.1, p=0.005). Reverse LV remodeling was demonstrated in 31 of the 54 patients eligible for this specific analysis (31/54, 57%): Both LV end-diastolic and end-systolic volumes indexed significantly decreased (both p=0.0001) as well as systolic pulmonary artery pressure (SPAP) (p=0.006). Ejection fraction increased from 33 ± 8% to 43 ± 8% (p<0.0001). Stress echocardiography was performed in a subgroup of eight patients. Mean mitral area at rest was 2.2 ± 0.3 cm² and did not change during stress. Cardiac output significantly increased in all patients during exercise. Although mean and peak transmitral gradients were 3.3 ± 1.3 and 8.1 ± 2.2 mmHg at rest and 6.6 ± 2.5 and 14.8 ± 3.9 mmHg under stress, respectively (both p<0.003), the increase in SPAP was not statistically significant (28 ± 3.0 vs 31 ± 7.5 mm Hg, p=0.17), revealing a preserved cardiac adaptation to exercise. CONCLUSIONS: The GeoForm ring is effective in relieving FMR in most of the patients with dilated cardiomyopathy. In presence of prevalent restricted motion of the posterior leaflet, recurrence of significant MR is more likely to occur. Clinically relevant mitral stenosis was not detected during exercise.

The clover technique for the treatment of complex tricuspid valve insufficiency: midterm clinical and echocardiographic results in 66 patients.

OBJECTIVE: This study assesses the results of the 'clover technique' (suturing together the middle point of the free edges of the tricuspid leaflets) for the treatment of tricuspid regurgitation (TR) due to severe prolapse or tethering. METHODS: From 2001, 66 patients with severe TR due to prolapsing or tethered leaflets underwent 'clover repair'. Annuloplasty was associated in 64 patients (97%). The aetiology of TR was degenerative in 52 cases (79%), post-traumatic in eight (12%) and secondary to dilated cardiomyopathy (DCM) in six (9%). The main mechanism of TR was prolapse/flail of one leaflet in 15 patients (23%), of two leaflets in 31 (47%) and of all three leaflets in 14 (21%). The remaining six patients (9%) presented with severe leaflets' tethering. RESULTS: Four deaths (6%) occurred during hospitalisation and one patient died 3.6 years after surgery. Survival was 91 + or - 4.1% at 5 years. Follow-up of the 62 hospital survivors was 100% complete (mean length 3.5 + or - 1.6 years, range 13 months-7.1 years). At the last echocardiogram, no or mild TR was detected in 55 (88.7%) patients, moderate (2+/4+) in six (9.6%) and severe (4+/4+) in one patient (1.6%). Mean tricuspid valve area and gradient were 4.3 + or - 0.6 cm(2) and 2.8 + or -1.4 mmHg. In six patients, stress echocardiography was performed and no signs of tricuspid stenosis were detected. At the multivariable analysis, the degree of TR at hospital discharge was identified as the only predictor of TR > or = 2+ at follow-up. CONCLUSIONS: Midterm clinical and echocardiographic results confirm the role of the 'clover technique' in the surgical treatment of TR due to lesions, which are unlikely to be effectively treatable by annuloplasty alone.