Left Ventricular Remodeling Shortly after Open Mitral Valve Replacement for Rheumatic Mitral Stenosis

Abstract Introduction: Left ventricular dysfunction after surgical treatment of mitral stenosis is uncommon. We intend to determine the pattern of left ventricular remodeling, shortly after open mitral valve replacement for rheumatic mitral stenosis, with in-hospital postoperative outcomes and the determinants of postoperative worsening of left ventricular ejection fraction. Methods: From January 2008 to January 2015, 107 adult patients with rheumatic mitral stenosis were submitted to open mitral valve replacement. Their mean age was 45±11 years and 93 (86.9%) were women. Left ventricular morphology and function were studied longitudinally with echocardiography. The end point was postoperative worsening of left ventricular ejection fraction, defined by a decrease of 10% compared to preoperative basal assessment. Determinants of worsening left ventricular ejection fraction were determined by multivariable logistic regression analysis. Results: The end point occurred in 18 patients (16.8%). We tested clinical and echocardiographic parameters to verify independent variables related to the decrease in postoperative ejection fraction. Lower body weight (P=0.005; odds ratio [OR]=0.89) and smaller preoperative mitral valve area (P=0.02; OR=0.02) were independent predictors of left ventricular dysfunction. These patients presented higher mortality and morbidity rates. Conclusion: Left ventricular remodeling patterns differed among patients with predominant rheumatic mitral stenosis undergoing open mitral valve replacement. Lower preoperative body weight and mitral valve area were independent determinants of deteriorating ejection fraction with increased end-systolic volumes, indicating that this specific problem may occur in anthropometric smaller patients with more extensive rheumatic disease.

Coexistent mitral stenosis and left circumflex coronary artery to left atrial fistula in a patient with severe pulmonary hypertension

Abstract Coronary artery to left atrial fistula is rare in patients with mitral stenosis. We report an interesting case of a patient with concomitant mitral valve stenosis and coronary fistulae, originating from the left circumflex artery and drained into the left atrium with two terminal orifices.

Comparison of early and long-term follow-up results of percutaneous mitral balloon valvuloplasty and mitral valve replacement

SUMMARY BACKGROUND: Percutaneous mitral balloon valvuloplasty and mitral valve replacement have been the treatment options for mitral stenosis for several years, however, studies that compare these two modalities are very rare in the literature. ObjectIve: In this article, we aim to investigate the comparison of clinical results of percutaneous mitral balloon valvuloplasty and mitral valve replacement. Methods: 527 patients with rheumatic mitral stenosis, treated with percutaneous mitral balloon valvuloplasty or mitral valve replacement (276 patients with percutaneous mitral balloon valvuloplasty and 251 patients with mitral valve replacement) from 1991 to 2012 were evaluated. The demographic characteristics, clinical, echocardiographic and catheterization data of patients were evaluated retrospectively. The results of early and late clinical follow-up of patients after percutaneous mitral balloon valvuloplasty and mitral valve replacement were also evaluated. Results: The mean follow-up time of the percutaneous mitral balloon valvuloplasty group was 4.7 years and, for the mitral valve replacement-group, it was 5.45 years. The hospital stay of the percutaneous mitral balloon valvuloplasty group was shorter than that of the mitral valve replacement group (2.02 days vs 10.62 days, p<0.001). The hospital mortality rate of percutaneous mitral balloon valvuloplasty and mitral valve replacement were 0% and 2% respectively (p=0.024). In the percutaneous mitral balloon valvuloplasty group, early postprocedural success rate was 92.1%. The event-free survival of percutaneous mitral balloon valvuloplasty and mitral valve replacement was found to be similar. While reintervention was higher in percutaneous mitral balloon valvuloplasty-group (p<0.001), mortality rate was higher in mitral valve replacement-group (p<0.001). Conclusion: Percutaneous mitral balloon valvuloplasty seems to be more advantageous than mitral valve replacement due to low mortality rates, easy application of the procedure and no need for general anesthesia.

Un caso clínico de implante valve in valve mitral: nuevo horizonte en el tratamiento de la disfunción valvular protésica / A clinical case of mitral valve in valve implant: new skyline in the treatment of prosthetic valve dysfunction / Presentação de um caso clínico do valve in valve mitral: um novo horizonte no tratamento da disfunção valvular protética

La disfunción valvular protésica es cada vez más frecuente debido al envejecimiento de la población portadora de bioprótesis y se presenta como un desafío en el momento de su diagnóstico, valoración y tratamiento. Aplicar un enfoque imagenológico multimodal es fundamental para su manejo. Respecto al tratamiento, surge como nueva alternativa un procedimiento mínimamente invasivo de sustitución valvular percutánea, denominado valve in valve, principalmente en pacientes con riesgo quirúrgico elevado. Presentamos uno de los primeros casos locales de implante percutáneo de prótesis mitral transeptal dentro de una bioprótesis mitral quirúrgica disfuncionante.

Prosthetic valve dysfunction is increasingly common due to the aging of the bioprosthesis-bearing population, and it presents a challenge at the time of diagnosis, evaluation, and treatment. A multimodal imaging approach is essential for its management. In relation to treatment, a minimally invasive percutaneous valve replacement procedure called valve in valve arises as a new alternative, mainly in patients with high surgical risk. We present one of first local cases of percutaneous implantation of a transseptal mitral prosthesis within a dysfunctional surgical mitral bioprosthesis.

A disfunção valvular protética é cada vez mais comum devido ao envelhecimento da população portadora de biopróteses e representa um desafio no momento do diagnóstico, avaliação e tratamento. A multimodalidade da imagem cardiovascular é essencial para sua avaliação. Em relação ao tratamento, um procedimento de troca valvular percutânea minimamente invasivo, denominado valve in valve, surge como uma nova alternativa, principalmente em pacientes com alto risco cirúrgico. Apresentamos um dos primeiros casos realizados no Uruguai de implantação percutânea de prótese mitral transeptal dentro de bioprótese mitral cirúrgica disfuncional.

Estenosis mitral con calcificación severa del anillo mitral: reemplazo mitral con prótesis OnX Conform en posición supraanular / Mitral stenosis with severe annular calcification: mitral valve replacement with an OnX Conform prosthesis in a supra annular position

Abstract A 68-year-old man previously subjected to radiotherapy had a prior aortic valve replacement due de radiation induced calcification of the aortic valve. Presently the patient developed severe calcification of the mitral valve ring leading to critical mitral valve stenosis. A supra annular implantation of an On X Conform valve was successfully achieved. The clinical course was uneventful, and the echocardiographic evaluation demonstrated a normal function of the valve. Different alternatives for the surgical management of this complication are discussed.

Minithoracotomy vs. conventional mitral valve surgery for rheumatic mitral valve stenosis: a single-center analysis of 128 patients

Abstract Objective: To compare the in-hospital outcomes of a right-sided anterolateral minithoracotomy with those of median sternotomy in patients who received a mitral valve replacement (MVR) because of rheumatic mitral valve stenosis (RMS). Methods: This is a retrospective analysis of 128 patients (34% male) with RMS between 2011 and 2015. The median age was 53 years (45; 56). The mean ejection fraction was 58.4±6.3%. All the subjects were divided into two groups - Group 1 contained 78 patients who underwent MVR via minithoracotomy (MT-MVR), while Group 2 contained 50 patients who underwent MVR via median sternotomy (S-MVR). Results: In the MT-MVR group, a mechanical prosthesis was implanted in 72% of cases, while it was implanted in 90% of cases in the S-MVR group (P=0.01). The duration of myocardial ischemia was similar (MT-MVR, 77±24 min; S-MVR, 70±18 min) (P=0.09). However, the cardiopulmonary bypass time was lower in the S-MVR group than in the MT-MVR group (99±24 min and 119±34 min, respectively) (P≤0.001). There was no difference in the duration of mechanical ventilation, intensive care unit stay, and hospitalization period. Postoperative blood loss was lower in the MT-MVR group (P≤0.001) than in the S-MVR group. There are no statistically significant differences in postoperative complications (superficial wound infection, stroke, delirium, pericardial tamponade, pleural puncture, acute kidney insufficiency, and implantation of pacemaker). The overall in-hospital mortality was 3.9% (P=0.6) Conclusion: The minimally invasive approach for RMS is feasible and has an excellent cosmetic effect without increasing the risk of surgical complications.

N-terminal-pro-brain natriuretic peptide, a surrogate biomarker of combined clinical and hemodynamic outcomes following percutaneous transvenous mitral commissurotomy

Aim: To examine the relationship between plasma levels of N-terminal-proB type natriuretic peptide [NT-proBNP] and various echocardiographic and hemodynamic parameters in patients with mitral stenosis undergoing percutaneous transvenous mitral commissurotomy [PTMC]

Materials and methods: The study population consisted of 100 patients with rheumatic mitral stenosis who underwent PTMC. NT-proBNP levels in these patients were measured before PTMC and 48 hours after PTMC. These levels were then correlated with various echocardiographic and hemodynamic parameters measured before and after PTMC

Results: Eighty-one percent of the study population were women, and the most common presenting symptom was dyspnea which was present in 94% of the patients. Dyspnea New York Heart Association class correlated significantly with baseline NT-proBNP levels [r = 0.63; p < 0.01]. The plasma NT-proBNP levels in these patients increased as echocardiogram signs of left atrial enlargement and right ventricular hypertrophy developed [r = 0.59, p < 0.01]. Patients in atrial fibrillation had significantly higher NT-proBNP levels than patients in sinus rhythm. Baseline NT-proBNP levels correlated significantly with left atrial volume [r = 0.38; p < 0.01], left atrial volume index [r = 0.45; p < 0.01], systolic pulmonary artery pressures [r = 0.42; p < 0.01], and mean pulmonary artery pressures [r = 0.41; p < 0.01]. All patients who underwent successful PTMC showed a significant decrease in NT-proBNP [decreased from a mean 763.8 pg/mL to 348.6 pg/mL] along with a significant improvement in all echocardiographic and hemodynamic parameters [p < 0.01]. The percent change in NT-proBNP correlated significantly with the percent improvement noted with left atrial volume [r = 0.39; p < 0.01], left atrial volume index [r = 0.41; p < 0.01], systolic [r = 0.32, p < 0.01], and mean pulmonary artery pressures [r = 0.31, p < 0.01]

Conclusions: The decrease in NT-proBNP levels following PTMC reflects an improvement in clinical and hemodynamic status; hence, it is reasonable to suggest that NT-proBNP is helpful in evaluating the response to PTMC

Rotura espontánea del velo posterior de una prótesis biológica mitral / Spontaneous rupture of the posterior leaflet of a mitral bioprosthesis

Introducción: Mujer de 66 anos portadora de Prótesis biológica en posición mitral que presenta rotura del velo posterior de la válvula protésica a 2 años de su cirugía.

A 66 year old woman with a bioprosthesis in the mitral position presented with a rupture of the posterior leaflet of the prosthetic valve 2 years following surgery.

Resultados a largo plazo de la valvuloplastía mitral con balón / Long term results of mitral balloon valvuloplasty

Background: Mitral balloon valvuloplasty (MBV) is the therapy of choice for the treatment of symptomatic mitral stenosis with suitable anatomy. Although its short and mid-term results are favorable, there is a paucity of information about long-term follow-up. Aim: To assess the late results of MBV. Material and Methods: A cohort of 225 patients aged 8 to 20 years who were subjected to a MBV from 1989 to 2001, was studied. All variables at the time of the procedure, short and long-term results and major events during follow-up (new mitral intervention and mortality) were recorded. Uni and multivariate analysis were used to assess prognosis. Results: The mean follow-up lapse was 13.5 years (range 8 to 20 years). During this period, 88 patients (39.1%) remained event-free and in acceptable functional capacity. Eight percent died, 8% required a second MBV and 43.5% required a surgical mitral valve replacement. A post-procedural area equal or greater to 1.9 cm² was associated with a greater likelihood of free-event survival (log rank test: p = 0.02/Cox proportional regression model: coefficient 0.54, p = 0.04). Conclusions: MBV is effective, although there is a high chance of new interventions in the long-term follow-up. A larger post-procedure mitral area is associated with a better prognosis.

Emergency mitral valve replacement for acute severe mitral regurgitation following balloon mitral valvotomy: Pathophysiology of hemodynamic collapse and peri-operative management issues.

Severe mitral regurgitation (MR) following balloon mitral valvotomy (BMV) needing emergent mitral valve replacement is a rare complication. The unrelieved mitral stenosis is compounded by severe MR leading to acute rise in pulmonary hypertension and right ventricular afterload, decreased coronary perfusion, ischemia and right ventricular failure. Associated septal shift and falling left ventricular preload leads to a vicious cycle of myocardial ischemia and hemodynamic collapse and needs to be addressed emergently before the onset of end organ damage. In this report, we describe the pathophysiology of hemodynamic collapse and peri‑operative management issues in a case of mitral valve replacement for acute severe MR following BMV.

Cardiac surgery during pregnancy: Continuous fetal monitoring using umbilical artery Doppler flow velocity indices.

The fetal death rate associated with cardiac surgery with cardiopulmonary bypass (CPB) is as high as 9.5‑29%. We report continuous monitoring of fetal heart rate and umbilical artery flow‑velocity waveforms by transvaginal ultrasonography and their analyses in relation to events of the CPB in two cases in second trimester of pregnancy undergoing mitral valve replacement. Our findings suggest that the transition of circulation from corporeal to extracorporeal is the most important event during surgery; the associated decrease in mean arterial pressure (MAP) at this stage potentially has deleterious effects on the fetus, which get aggravated with the use of vasopressors. We suggest careful management of CPB at this stage, which include partial controlled CPB at initiation and gradual transition to full CPB; this strategy maintains high MAP and avoids the use of vasopressors. Maternal and fetal monitoring can timely recognize the potential problems and provide window for the required treatment.

Evolução em longo prazo da valvoplastia mitral com balão único: fatores de risco para eventos maiores / Long-term outcomes of single ballon mitral valvuloplasty: riskfactors for major events

Fundamentos: A técnica do balão único é de mais baixo custo e tem resultados semelhantes à de Inoue. Objetivos: Analisar a evolução da valvoplastia mitral com balão único Balt e fatores de risco para óbito e eventos maiores (óbito, nova valvoplastia mitral por balão ou cirurgia valvar mitral). Métodos: O balão único foi usado em 256 procedimentos, com diâmetro máximo de 25 mm em5 (1,9 %) e de 30 mm em 251 (98,1 %) procedimentos. O período médio de seguimento foi 55±33 meses. Resultados: Encontrou-se no grupo do balão único: média de idade 38,0±12,6 anos; escore ecocardiográfico 7,2±1,5 pontos; escore ecocardiográfico >8, 32 (12,5 %);sexo feminino, 222 (86,7 %); ritmo sinusal, 215 (84,0 %); sobrevida no seguimento de 245 (95,7 %) e sobrevida livre de eventos maiores, 211 (83,4 %). Na análise multivariada predisseram independentemente óbito: idade ³50 anos e escore ecocardiográfico >8 e eventos maiores: área valvar mitral pós-procedimento <1,50 cm2; comissurotomia prévia e sexo masculino; e com sete variáveis predisseram independentemente óbito: idade ≥50 anos, escore ecocardiográfico >8 e cirurgiamitral na evolução. Conclusões: Predisseram óbito e/ou eventos maiores: idade ≥50 anos, escore ecocardiográfico >8,área valvar mitral pós-procedimento <1,50 cm2, comissurotomia prévia, sexo masculino e cirurgia mitral na evolução.

Background: The single ballon (SB) technique is a low-cost option with outcomes similar to the Inoue ballon. Objectives: To analyze the long term outcomes of SB Balt mitral valvuloplasty with risk factors for death and major events (death, further mitral ballon valvuloplasty, or mitralvalve surgery) Methods: The single ballon was used in 256 procedures, with maximum balloon diameters of 25 mm for 5 (1.9%) procedures and 30 mm for 251 (98.1%)procedures. The mean follow-up period was 55+-33 months. Results: The single balloon group presented: age38.0±12.6 years, echocardiographic score 7.2±1.5points, echocardiographic score >8.32 (12.5 %), female 222(86.7 %), sinus rhythm 215 (84.0 %), survival for 245(95.7 %) at the end of the follow-up period and survival with no major events for 211 (17.6 %). In a multivariate analysis, the independent death prediction factors were: age ≥50 years and echocardiographic score >8; major events: post-procedure <1.5 cm2 mitral valve area, prior commisurotomy and male; the seven independent death prediction variables were: age ≥50years, echocardiographic score >8 and mitral valve surgery during the follow-up period. Conclusions: Death or major event predictors were: age ≥50 years, echocardiographic score >8, post-procedure mitral valve area <1.50 cm2, prior commisurotomy, male and mitral valve surgery during the follow-up period.

A comparison of hemodynamic effects of levosimendan and dobutamine in patients undergoing mitral valve repair / replacement for severe mitral stenosis.

Aims and Objectives: We aimed to compare the hemodynamic effects of levosimendan and dobutamine in patients undergoing mitral valve surgery on cardiopulmonary bypass (CPB). Materials and Methods: Sixty patients were divided into 2 groups of 30 each. Group-L patients received levosimendan 0.1 μg/kg/min and Group-D patients received dobutamine 5 μg/kg/min while weaning off CPB. Additional inotrope and/or vasoconstrictor were started based on hemodynamic parameters. Hemodynamic data were collected at the end and at 30 minutes after CPB, thereafter at 6, 12, 24, and 36 hours post-CPB. Mean arterial pressure (MAP), central venous pressure (CVP), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI), and lactate levels were measured. Results: Group-L showed increased requirement of inotropes and vasoconstrictors. The SVRI, CVP, and MAP were reduced more in Group-L. The CI was low in Group-L in the initial period when compared to Group-D. Later Group-L patients showed a statistically significant increase in CI even after 12 hrs of discontinuation of levosimendan infusion. The HR was increased more in Group-D. Lactate levels, intensive care unit stay, and duration of ventilation were similar in both groups. Conclusions: Levosimendan 0.1 μg/kg/min compared to dobutamine 5 μg/kg/min showed more vasodilation and lesser inotropic activity in patients undergoing mitral valve surgery for mitral stenosis. Levosimendan compared to dobutamine showed a statistically significant increase in CI even after 12 hrs of discontinuation. The requirement of another inotrope or vasopressor was frequent in levosimendan group.

Hemi-fontan or bidirectional cavopulmonary shunt for right ventricular failure after mitral valve replacement and acute ascending aortic dissection: report of two cases

Right ventricular failure due to right coronary artery disease, right ventricular hypertrophy, stunning, abnormal septal motion, myocardial infarction, or non-homogeneous distribution of cardioplegia is an uncommon but serious complication of open heart surgery. We report a patient with severe right ventricular hypertrophy secondary to severe mitral valve stenosis and another patient with detachment of the right coronary artery due to the dissection of the ascending aorta. The patients developed right ventricular failure, which persisted after surgery and rendered weaning from cardiopulmonary bypass unsuccessful. Through a hemi-Fontan, or bidirectional cavopulmonary shunt, and an intra-aortic balloon pump, the patients were successfully weaned from cardiopulmonary bypass. This shunt may be an alternative to a right ventricular assist device in some patients with right ventricular failure. The long-term outcome and the indication of bi-directional cavopulmonary shunt has not been confirmed, although it is believed to be effective for saving the life of patients with low cardiac output and acute right ventricular failure. In our cases, six months following the operation, there was some degree of recovery of the right ventricular function. In long-term follow-up, however, it would be interesting for the authors to know if the improved right ventricular function, with better antegrade pulsatile flow in the pulmonary artery, in any way interferes with the functioning of the bidirectional cavopulmonary shunt

Gene expression of endothelin receptors in replaced rheumatic mitral stenotic valves / Expressão gênica de receptores de endotelina em valvas mitrais reumáticas estenóticas substituídas

OBJECTIVES: Rheumatic fever is a highly prevalent disease in Brazil, and it poses a major public health problem. It is the leading cause of acquired heart disease in childhood and adolescence. The aim of this study was to evaluate the gene expression of ET-3 and its receptors, in replaced rheumatic mitral valves. METHODS: We studied the gene expression of endothelin-3 (ET-3) and its receptors, endothelin receptor A and endothelin receptor B (ETr-A and ETr-B), in the rheumatic mitral valves of 17 patients who underwent valve replacement surgery. The samples also underwent a histological analysis. RESULTS: Our data showed that almost all patients, regardless of individual characteristics such as gender or age, expressed the endothelin receptor genes, but did not express the genes for ET-3. In quantitative analysis, the ETr-A/GAPDH mean ratio was 33.04 ± 18.09%; while the ETr-B/GAPDH mean ratio was 114.58 ± 42.30%. Regarding histopathological individual features, the frequency of fibrosis is 100%, 88.23% of mononuclear infiltrate, 52.94% of neovascularization, 58.82% of calcification and absence of ossification. CONCLUSION: The presence of receptors ETr-A and ETr-B in rheumatic mitral valves suggests its interaction with the system of circulating endothelins, particularly ETr-B (known for acting in the removal of excess endothelin) detected in a greater proportion, which could explain the lack of expression of endothelin in rheumatic mitral valve, process to be elucidated.

OBJETIVOS: A febre reumática é uma doença altamente prevalente no Brasil, e representa um importante problema de saúde pública. É a principal causa de cardiopatia adquirida na infância e adolescência. O objetivo deste estudo foi avaliar a expressão gênica de ET-3 e seus receptores, em valvas mitrais reumáticas substituídas. Métodos: Estudamos a expressão gênica de endotelina-3 (ET-3) e de seus receptores, receptor da endotelina A e receptor da endotelina B (ETr-A e ETr-B), nas valvas mitrais reumáticas de 17 pacientes que se submeteram à cirurgia de troca valvar. As amostras também foram submetidas à análise histológica. RESULTADOS: Nossos dados mostraram que praticamente todos os pacientes, independentemente de características individuais, como sexo ou idade, expressaram os genes de receptores de endotelina, porém não expressaram os genes para ET-3. Na análise quantitativa, a média da proporção ETr-A/GAPDH foi de 33,04 ± 18,09%; enquanto que a média da proporção ETr-B/GAPDH foi de 114,58 ± 42,30%. Em relação às características histopatológicas individuais, a frequência de fibrose foi de 100%, infiltrado mononuclear de 88,23%, neovascularização de 52,94%, calcificação de 58,82% e houve ausência de ossificação. CONCLUSÃO: A presença de receptores ETr-A e ETr-B em valvas mitrais reumáticas sugere sua interação com o sistema de endotelinas circulantes, particularmente ETr-B (reconhecido por atuar na remoção do excesso de endotelina), detectado em maior proporção, o que poderia explicar a ausência da expressão de endotelina em valva mitral reumática, processo a ser elucidado.

novel technique of multi-track percutaneous balloon mitral commissurotomy [PBMC]

Percutaneous balloon mitral commissurotomy [PBMC] has become treatment of choice for severe pliable rheumatic mitral valve stenosis [RMVS]. The multi-track system is a recent variant of the double-balloon technique which is easier through the use of a monorail balloon and only a simple, single guide wire approach. In the present study, we sought to use the Inoue metallic wire with multi-track balloon instead of the conventional multi- track wire will make the procedure safer and faster. We studied 62 consecutive patients [55 females] with significant symptomatic RMVS who underwent multi-track PBMC. They were randomized into 2 groups: the first group included 32 patients treated with the novel multi-track technique using the double coil Inoue metallic wire, and the second group includes 30 patients treated with the conventional multi-track technique. No statistically significant differences were found between both groups regarding any of the studied variables; apart from the pre-procedural MV area which was significantly lower in the novel-technique group compared to the conventional-technique group. None of the patients had cardiac tamponade, systemic thromboembolism or any groin complication. There were neither in-hospital deaths nor complications necessitating emergent cardiac surgery in both groups. This new technique achieves the double benefit of being safer and easier with Inoue wire and saving excess material with the multi-track system; which is more economic