RESUMEN
Introducción: En la estenosis aórtica sintomática grave (EASG), la alteración del strain global longitudinal sistólico (SGLS) tendría correlación con las modificaciones de la histoarquitectura y podría identificar compromiso contráctil temprano en pacientes con fracción de eyección conservada (FEyC). Objetivo: Analizar el SGLS, el volumen de colágeno (VC), el área miocitaria (ArMi) y el compromiso contráctil en pacientes con EASG y FEyC. Material y métodos: Se incorporaron 26 pacientes con EASG y FEyC (edad 67 ± 11 años, 53% hombres). Se realizaron un estudio hemodinámico preoperatorio y una biopsia endomiocárdica intraoperatoria para determinar el VC y el ArMi. Se identificaron tres grupos de pacientes: G1, hipertrofia ventricular izquierda (HVI) compensada sin enfermedad coronaria (n = 8); G2, HVI descompensada sin enfermedad coronaria (n = 7) y G3, HVI descompensada con enfermedad coronaria (n = 11). El SGLS se normalizó por volumen sistólico, estrés meridional de fin de sístole (δ) y diámetro de fin de diástole (DFD). Resultados: G1, G2 y G3, sin diferencias en volumen sistólico, δ y DFD y con diferencias en VC (%) (G1: 4,7 ± 1,2; G2: 8,4 ± 1,2; G3: 11,0 ± 3,0; p < 0,01), ArMi (mm²) (G1: 328,7 ± 66,2; G2: 376,7 ± 21,9; G3: 385,0 ± 13,0; p = 0,01), PFDVI (mm Hg) (G1: 13,1 ± 1,5; G2: 19,0 ± 3,8; G3: 23,6 ± 5,8; p < 0,01), +dP/dt máx (mm Hg/seg / PFDVI, mm Hg) (G1: 176,4 ± 45,5; G2: 89,6 ± 20,1; G3: 113,1 ± 43,7; p < 0,01), SGLS (%) (G1: -17,9 ± 4,2; G2: -13,5 ± 2,5; G3: -13,6 ± 3; p = 0,021). El SGLS se correlacionó con VC y PFDVI y hubo tendencia con un índice de contractilidad (+dP/dt máx mm Hg/seg / PFDVI, mm Hg). Conclusiones: Las alteraciones del SGLS en pacientes con EASG y FEyC son expresión de alteraciones estructurales del miocardio relacionadas con incremento del VC, asociado con un aumento de la PFDVI y con probable falla miocárdica contráctil.
Background: In severe symptomatic aortic stenosis (SSAS) altered global longitudinal systolic strain (GLSS) would correlate with changes in myocardial histological architecture and could identify early contractile involvement in patients with preserved ejection fraction (PEF). Objective: The aim of this study was to analyze GLSS, collagen volume (CV), myocyte area (MyAr) and contractile involvement in patients with SSAS and PEF. Methods: Twenty six patients with SSAS and PEF (67±11 years old, 53% male) were included in the study. A preoperative hemodynamic study and an intraoperative endomyocardial biopsy were performed to determine CV and MyAr. Three groups of patients were identified: G1: compensated left ventricular hypertrophy (LVH) without coronary disease (n=8); G2: decompensated LVH without coronary disease (n=7) and G3: decompensated LVH with coronary disease (n=11). GLSS was normalized by stroke volume, meridional end-systolic wall stress (δ) and end-diastolic diameter (EDD). Results: No significant differences in stroke volume, δ and EDD were observed between groups G1, G2 and G3. Differences between groups were observed in: CV (%) (G1: 4.7 ± 1.2, G2: 8.4 ± 1.2, G3: 11.0 ± 3.0; p < 0.01), MyAr (mm²) (G1: 328.7 ± 66.2, G2: 376.7 ± 21.9, G3: 385.0 ± 13.0; p = 0.01), LVEDP (mm Hg) (G1: 13.1 ± 1.5, G2: 19.0 ± 3.8, G3: 23.6 ± 5.8; p < 0.01), +dP/dt max (mm Hg/sec / LVEDP, mm Hg) (G1: 176.4 ± 45.5, G2: 89.6 ± 20.1, G3: 113.1 ± 43.7; p < 0.01), and GLSS (%) (G1: -17.9 ± 4.2, G2: -13.5 ± 2.5, G3: -13.6 ± 3; p = 0.021). GLSS correlated with CV and LVEDP and it evidenced a trend to correlate with a contractility index (+dP/dt max mm Hg/s / LVEDP, mm Hg). Conclusions: Altered GLSS in patients with SSAS and PEF expresses myocardial structural changes related to increase in C V, which is associated with enhanced LVEDP and probable myocardial contractile failure.
RESUMEN
Introdução: A história natural da insuficiência mitral associa-se a décadas de remodelação ventricular esquerda com fibrose intersticial. A fronteira entre o processo adaptativo e a miocardiopatia dilatada demanda avaliação clínico-histológica. Atualmente, sabe-se que o melhor método empregado para quantificar as alterações decorrentes do remodelamento que acomete o ventrículo esquerdo é a biópsia miocárdica, que analisa a doença, somente após a cirurgia ou no post mortem. O presente estudo visa avaliar a fibrose miocárdica associada à insuficiência mitral crônica, através de estudo pela Ressonância Magnética, de maneira não invasiva, precoce e rápida. Objetivos: Avaliar a capacidade e a aplicabilidade da ressonância magnética cardíaca de detectar a fibrose miocárdica na insuficiência mitral crônica importante, tendo como referência a biópsia miocárdica. Métodos: Foram selecionados 52 pacientes portadores de IM crônica pura ou associada a estenose mitral leve, com PVM e DR, e com indicação cirúrgica. Todos os pacientes foram reavaliados pelo EcoDopplercardiograma e realizaram ressonância magnética cardíaca para avaliação da função ventricular, volumes e índice de massa ventricular esquerda, através da cine-ressonância e pela técnica do realce tardio miocárdico, com injeção de 0,2 mmol/kg de contraste gadolínio para a detecção de FM, sendo submetidos a cirurgia de plástica ou troca de válvula mitral com bióspsias miocárdicas, retiradas de locais padrão, na parede lateral do ventrículo esquerdo. Todas foram coradas pela técnica do hematoxilinaeosina, e as positivas para FM, confirmadas pelo corante picrossirius, que cora colágeno, e quantificadas pelo aparelho do quantimet. Resultados: Os pacientes foram divididos em quatro grupos, conforme a RM e a biópsia. A RM diagnosticou FM em 18 pacientes, concordantes com a BM (RMC/BM +). A RM foi negativa para FM em 33 pacientes, sendo 28 concordantes com a BM (RMC/BM -). Observou-se discordância de RM com a BM...
Introduction: The natural history of mitral insufficiency (MI) is associated to decades of left ventricular remodelation with intersticial fibrosis. The frontier between adaptative process and dilatade miocardiopaty needs clinic and histologic evaluation. Now a days , we know that the best method to quantify the alterations of remodelation in left ventricule is myocardial biopsies which analyses the illness only after surgery or post morten. This actual study aims to evaluate myocardial fibrosis associated with cronic MI, through the study with magnetic resonance (MR), in a not invasive, early and quickly way. Objectives: Evaluate capacity and applicability of the magnetic resonance in detection of myocardial fibrosis in chronic important mitral insufficiency in reference with myocardial biopsis. Methods: It was selected 52 patients with pure chronic MI or associated with mild mitral stenosis, with cirurgical indication. All of the patients were reevaluated by EcoDopplercardiogram and it was done cardiac MR to evaluate ventricular function, volumes and left ventricular mass rate through MR cine and myocardial late realce techinique with 0,2 mmol/Kg with gadoline contrast and myocardial fibrosis (MF) detection and being undergone plastic or mitral valvular changes surgery with myocardial biopsis (MB) were taken from the left ventricular lateral wall. All of them were colored with hematoxilin eosine and the positives were confirmated with picrossirius and quantified with quantimet device. Results: Patients were divided in four groups according to MR and biopsies. MR diagnosticated MF in 18 patients agreed with MB (MR / MB +). MR was negative for MF in 33 patients where 28 agreed with MB (MR / MB -). We observated discordance with MR and MB in 7 cases false negatives (MR- /MB+). The sensibility of MR to fibrosis was 72%, specificity was 100% and acurace was 86,3%. In the distinct groups studied, we see sensibility, specifity and acure were 64,7%...