Fisiopatología y pronóstico de la deformación longitudinal regional durante el eco estrés con dipiridamol / Pathophysiology and Prognosis of Apical Longitudinal Strain During Dipyridamole Stress Echocardiography

RESUMEN Introducción: El strain longitudinal apical regional permite corroborar el diagnóstico de alteraciones regionales de la motilidad parietal sobre una base cuantitativa, pero faltan datos sobre su valor pronóstico a largo plazo. Objetivos: Evaluar el correlato fisiológico y el valor pronóstico del strain longitudinal apical en el eco estrés con dipiridamol frente a la motilidad parietal. Métodos: Estudio retrospectivo, que incluyó 150 pacientes remitidos para eco estrés con dipiridamol. Se evaluó el strain longitudinal apical, la reserva coronaria (RC) de la arteria descendente anterior y el análisis visual de la motilidad parietal. Los pacientes se dividieron en dos grupos. Grupo1: pacientes con strain longitudinal apical normal y Grupo 2: con strain anormal. Se realizó seguimiento por 36 ± 9,3 meses. Evento mayor fue definido como: muerte, infarto de miocardio, revascularización e internación por causa cardíaca. Resultados: Fueron incluidos en el análisis 142 pacientes (8 pacientes fueron excluidos por ventana ultrasónica subóptima), 87 (61,3%) en el Grupo 1 y 55 (38,7%) en el Grupo 2. No hubo diferencias en el strain longitudinal apical en reposo entre ambos grupos. Durante el apremio, los pacientes del Grupo1 evidenciaron mejor motilidad parietal visual y una RC más alta (p < 0,001). La RC y los cambios del strain longitudinal apical presentaron una correlación positiva (coeficiente r de Pearson = 0,89, p < 0,0001). En el seguimiento hubo 24 eventos mayores. Los pacientes del Grupo1 tuvieron una mejor supervivencia libre de eventos (p<0,01) y el strain longitudinal apical demostró ser un predictor independiente de evento, mejor que el análisis de motilidad parietal (p = 0,002 vs p = 0,1), en el análisis de regresión logística. Conclusiones: El strain longitudinal apical tiene muy buena correlación con: la reserva de velocidad del flujo coronario y se asocia mejor con el pronóstico a largo plazo. El strain longitudinal apical anormal durante el eco dipiridamol predijo un peor resultado, independientemente del análisis visual de la motilidad parietal.

ABSTRACT Background: Regional apical longitudinal strain can corroborate the diagnosis of regional wall motion abnormalities on a quantitative basis, but data on long-term prognostic value are lacking. Objectives: To evaluate the physiological correlate and the prognostic value of apical longitudinal strain versus wall motility during dipyridamole stress echocardiography. Methods: Retrospective study, which included 150 patients referred for dipyridamole stress echocardiography. Apical longitudinal strain, anterior descending artery coronary reserve, and visual analysis of wall motility were evaluated. Patients were divided into two groups. Group 1: patients with normal apical longitudinal strain, and Group 2: abnormal strain. Follow-up was carried out for 36 ± 9.3 months. Major event was defined as: death, myocardial infarction, revascularization and hospitalization for cardiac causes. Results. Eighty-seven patients (61.3%) in Group 1 and 55 (38.7%) patients in Group 2 were included (8 patients were excluded due to a suboptimal ultrasound window). There were no differences in apical longitudinal strain at rest between the groups. During the stress, Group 1 patients showed better visual wall motility and a higher coronary reserve (p < 0.001). The coronary reserve showed a linear correlation with the changes in the apical longitudinal strain (Pearson's correlation coefficient 0.89, p < 0.0001). At follow-up, there were 24 major events. Group 1 patients had better event-free survival (p < 0.01) and apical longitudinal strain proved to be a better independent event predictor than wall motion analysis (p = 0.002 vs p = 0.1) in logistic regression analysis. Conclusions: Apical longitudinal strain has a very good correlation with physiological standards -coronary flow velocity reserve- and its association with long-term prognosis is better. Abnormal apical longitudinal strain during dipyridamole stress echocardiography predicted a worse outcome, regardless of visual wall motion analysis.

Long Term Prognostic Value of Contractile Reserve Assessed by Global Longitudinal Strain in Patients with Asymptomatic Severe Aortic Stenosis.

BACKGROUND: Left ventricle (LV) global longitudinal strain (GLS) at rest has shown prognostic value in patients (pts) with severe aortic stenosis (SAS). Contractile reserve (CR) during exercise stress echo (ESE) estimated via GLS (CR-GLS) could better stratify the asymptomatic patients who could benefit from early intervention. AIMS: To determine the long-term prognostic value of CR-GLS in patients with asymptomatic SAS with an ESE without inducible ischemia. Additionally, to compare the prognostic value of CR assessed via ejection fraction (CR-EF) and CR-GLS. METHODS: In a prospective, single-center, observational study between 2013 and 2019, 101 pts with asymptomatic SAS and preserved left ventricular ejection fraction (LVEF) > 55% were enrolled. CR was considered present with an exercise-rest increase in LVEF (Simpson's rule) ≥ 5 points and > 2 absolute points in GLS. Patients were assigned to 2 groups (G): G1: 56 patients with CR-GLS present; and G2: 45 patients CR-GLS absent. All patients were followed up. RESULTS: G2 Patients were older, with lower exercise capability, less aortic valve area (AVA), a higher peak aortic gradient, and less LVEF (71.5% ± 5.9 vs. 66.8% ± 7.9; p = 0.002) and GLS (%) at exercise (G1: -22.2 ± 2.8 vs. G2: -18.45 ± 2.4; p = 0.001). During mean follow-up of 46.6 ± 3.4 months, events occurred in 45 pts., with higher incidence in G2 (G2 = 57.8% vs. G1 = 42.2%, p < 0.01). At Cox regression analysis, CR-GLS was an independent predictor of major cardiovascular events (HR: 1.98, 95% CI 1.09-3.58, p = 0.025). Event-free survival was lower for patients with CR-GLS absent (log rank test p = 0.022). CR-EF was not outcome predictive (log rank test p 0.095). CONCLUSIONS: In patients with asymptomatic SAS, the absence of CR-GLS during ESE is associated with worse prognosis. Additionally, CR-GLS was a better predictor of events than CR-EF.

Feasibility and functional correlates of left atrial volume changes during stress echocardiography in chronic coronary syndromes.

An enlarged left atrial volume index (LAVI) at rest mirrors increased LA pressure and/or impairment of LA function. A cardiovascular stress may acutely modify left atrial volume (LAV) within minutes. Aim of this study was to assess the feasibility and functional correlates of LAV-stress echocardiography (SE) Out of 514 subjects referred to 10 quality-controlled labs, LAV-SE was completed in 490 (359 male, age 67 ± 12 years) with suspected or known chronic coronary syndromes (n = 462) or asymptomatic controls (n = 28). The utilized stress was exercise in 177, vasodilator in 167, dobutamine in 146. LAV was measured with the biplane disk summation method. SE was performed with the ABCDE protocol. The intra-observer and inter-observer LAV variability were 5% and 8%, respectively. ∆-LAVI changes (stress-rest) were negatively correlated with resting LAVI (r = - 0.271, p < 0.001) and heart rate reserve (r = -.239, p < 0.001). LAV-dilators were defined as those with stress-rest increase ≥ 6.8 ml/m2, a cutoff derived from a calculated reference change value above the biological, analytical and observer variability of LAVI. LAV dilation occurred in 56 patients (11%), more frequently with exercise (16%) and dipyridamole (13%) compared to dobutamine (4%, p < 0.01). At multivariable logistic regression analysis, B-lines ≥ 2 (OR: 2.586, 95% CI = 1.1293-5.169, p = 0.007) and abnormal contractile reserve (OR: 2.207, 95% CI = 1.111-4.386, p = 0.024) were associated with LAV dilation. In conclusion, LAV-SE is feasible with high success rate and low variability in patients with chronic coronary syndromes. LAV dilation is more likely with reduced left ventricular contractile reserve and pulmonary congestion.

Lung Ultrasound and Pulmonary Congestion During Stress Echocardiography.

OBJECTIVES: The purpose of this study was to assess the functional and prognostic correlates of B-lines during stress echocardiography (SE). BACKGROUND: B-profile detected by lung ultrasound (LUS) is a sign of pulmonary congestion during SE. METHODS: The authors prospectively performed transthoracic echocardiography (TTE) and LUS in 2,145 patients referred for exercise (n = 1,012), vasodilator (n = 1,054), or dobutamine (n = 79) SE in 11 certified centers. B-lines were evaluated in a 4-site simplified scan (each site scored from 0: A-lines to 10: white lung for coalescing B-lines). During stress the following were also analyzed: stress-induced new regional wall motion abnormalities in 2 contiguous segments; reduced left ventricular contractile reserve (peak/rest based on force, ≤2.0 for exercise and dobutamine, ≤1.1 for vasodilators); and abnormal coronary flow velocity reserve ≤2.0, assessed by pulsed-wave Doppler sampling in left anterior descending coronary artery and abnormal heart rate reserve (peak/rest heart rate) ≤1.80 for exercise and dobutamine (≤1.22 for vasodilators). All patients completed follow-up. RESULTS: According to B-lines at peak stress patients were divided into 4 different groups: group I, absence of stress B-lines (score: 0 to 1; n = 1,389; 64.7%); group II, mild B-lines (score: 2 to 4; n = 428; 20%); group III, moderate B-lines (score: 5 to 9; n = 209; 9.7%) and group IV, severe B-lines (score: ≥10; n = 119; 5.4%). During median follow-up of 15.2 months (interquartile range: 12 to 20 months) there were 38 deaths and 28 nonfatal myocardial infarctions in 64 patients. At multivariable analysis, severe stress B-lines (hazard ratio [HR]: 3.544; 95% confidence interval [CI]: 1.466 to 8.687; p = 0.006), abnormal heart rate reserve (HR: 2.276; 95% CI: 1.215 to 4.262; p = 0.010), abnormal coronary flow velocity reserve (HR: 2.178; 95% CI: 1.059 to 4.479; p = 0.034), and age (HR: 1.031; 95% CI: 1.002 to 1.062; p = 0.037) were independent predictors of death and nonfatal myocardial infarction. CONCLUSIONS: Severe stress B-lines predict death and nonfatal myocardial infarction. (Stress Echo 2020-The International Stress Echo Study [SE2020]; NCT03049995).

El comportamiento del strain longitudinal regional depende de la reserva coronaria en un análisis simultáneo durante el eco-estrés con dipiridamol / The Behavior of Regional Longitudinal Strain Depends on Coronary Flow Reserve in a Simultaneous Analysis during Dipyridamole Stress Echocardiography

RESUMEN Introducción: Está poco estudiado el comportamiento del strain longitudinal regional y global en relación al valor de la reserva coronaria. Objetivos: Comparar el comportamiento del strain longitudinal apical y global con el valor de la reserva coronaria de la arteria descendente anterior y secundariamente comparar estas respuestas con el análisis visual de la motilidad parietal durante el eco-estrés con dipiridamol. Material y métodos: Estudio retrospectivo de 179 pacientes (edad 68,7 ± 7,8), 90 hombres (50,3%). En el pico del efecto de dipiridamol, se midió la reserva coronaria, simultáneamente al strain longitudinal y el análisis visual de la contractilidad. Se organizó a los pacientes en dos grupos: grupo 1: reserva coronaria ≥ 2 y grupo 2: < 2. Strain apical se definió como el promedio de 4 segmentos apicales y global de los 17 segmentos. Se consideró normal a todo incremento del strain. Resultados: Se incluyeron 113 pacientes (63,12%) en el grupo 1 y 66 (36,87%) en el grupo 2. Strain apical: el 96,77% del grupo 1 incrementaron su valor con el apremio, mientras que, en el grupo 2, el 95,31% presentaron una caída (p < 0,0001). Strain global: el 82,8% del grupo 1 presentaron incremento de sus valores, en cambio, en el grupo 2, el 78,8% empeoraron (p < 0,01). Análisis de la motilidad parietal posdipiridamol: el 96,46% del grupo 1 tenían motilidad parietal conservada y el 54,5% del grupo 2 (solo en 4 pacientes aumentó el strain apical). Conclusiones: Se comprobó una estrecha correlación entre la reserva coronaria y el strain longitudinal. El strain longitudinal apical resultó ser superior del global. El strain apical demostró tener una mejor correlación con la reserva coronaria que con el análisis visual de la contractilidad.

ABSTRACT Background: The behavior of regional and global longitudinal strain in relation to the value of the coronary reserve is poorly studied. Objectives: Compare the behavior of the Apical and global longitudinal Strain with the value of the coronary reserve of the anterior descending artery and as a secondary aim compare these responses with the visual analysis of parietal motility during Echo Stress with Dipyridamole. Materials and methods: Retrospective study of 179 patients (age 68.7±7.8), 90 patients (50.3%) were men. At the peak of the dipyridamole effect, the coronary reserve was measured, simultaneously with the Longitudinal Strain and the visual analisis of contractility. Two groups were divided: Group 1: Coronary reserve ≥2 and Group 2: <2. Apical Strain was defined as the average of 4 apical segments and global as the average of the 17 segments. It was considered normal any increased of deformation. Results: 113 patients (63.12%) were included in Group 1 and 66 (36.87%) in Group 2. Strain Apical: 96.77% of Group 1 increased their strain values with the stress, while in group 2, 95.31% presented a worsening strain values (p<0.0001). Global Strain: 82.8% of Group 1 had an increase in their values, while in Group 2, 78.8% showed worsening (p<0.01). Post Dipyridamole parietal Motility Analysis: 96.46% of Group 1 had preserved parietal motility and only 54.5% of Group 2 (4 patients had increased apical Strain in this group). Conclusions: There was a close correlation between the coronary reserve of the anterior descending artery and the contractile reserve evaluated by regional apical longitudinal strain of the 4 apical segments, which was superior to the use of global strain. The Apical Strain showed a better correlation with ADA coronary reserve than with the visual analysis of contractility.

Coronary flow velocity reserve during pharmacologic stress echocardiography with normal contractility adds important prognostic value in diabetic and nondiabetic patients.

BACKGROUND: Coronary flow velocity reserve (CFVR) increases the diagnostic sensitivity of stress echocardiography. The aim of this study was to evaluate the prognostic value of CFVR in patients without new wall motion abnormalities during pharmacologic stress echocardiography. METHODS: The outcomes of 651 patients with normal wall motion response during stress echocardiography with dobutamine up to 50 µg/kg/min (n = 351) or dipyridamole up to 0.84 mg/kg over 4 min (n = 300) were evaluated. CFVR was calculated simultaneously in the distal territory of the left anterior descending coronary artery. CFVR ≥ 2 was defined as normal. Major events considered during follow-up were cardiovascular death, myocardial infarction, and late myocardial revascularization. RESULTS: Normal CFVR was recorded in 523 patients and reduced CFVR in 128. During a mean follow-up period of 34.6 ± 18 months, 48 major events occurred, in 25 patients (4.8%) with normal and 23 patients (18%) with reduced CFVR; event-free survival was significantly different between patients with normal versus abnormal CFVR (P < .0001). Diabetes increased risk only in patients with abnormal CFVR (P = .05). In the multivariate analysis, CFVR and history of smoking were the only independent predictors of combined morbidity and mortality. Abnormal CFVR was associated with a higher event rate, independently of the pharmacologic stress technique used. The event hazard ratio was inversely proportional to CFVR. CONCLUSIONS: CFVR was an independent predictor of mortality after pharmacologic stress echocardiography with normal wall motion, and the degree of decrease was associated with increased risk. Diabetes worsened prognosis only with abnormal CFVR.

Realidad de la cirugía cardíaca en la República Argentina: Registro CONAREC XVI / Real Facts in Cardiovascular Surgery in Argentina. The XVI CONAREC Registry

Introducción Los dos grandes registros multicéntricos de cirugía cardíaca realizados en la Argentina, CONAREC y ESMUCICA, datan de más de 10 años. Considerando los avances médicos y quirúrgicos de la última década, surgió la necesidad de realizar un nuevo registro nacional, prospectivo y multicéntrico para conocer las características, la evolución, las complicaciones y los predictores de mortalidad de los pacientes sometidos a cirugía cardíaca. Objetivos Conocer el perfil epidemiológico, la modalidad quirúrgica y la evolución posoperatoria de los pacientes sometidos a cirugía cardíaca en la Argentina. Material y métodos Registro prospectivo, consecutivo y multicéntrico realizado en 49 centros cardioquirúrgicos de la República Argentina por residentes de cardiología. Se analizaron las características y la evolución de 2.553 pacientes sometidos a cirugía cardíaca entre septiembre de 2007 y octubre de 2008: 1.465 (57,4%) a cirugía coronaria, 359 (14,1%) a reemplazo valvular aórtico, 169 (6,6%) a cirugía valvular mitral, 312 (12,2%) a cirugía combinada coronariovalvular y 248 (9,7%) a otros procedimientos. Resultados Hubo predominio de hombres (74,9%); la edad promedio fue de 63 ± 11 años. La prevalencia de diabetes fue del 24,9%, la de hipertensión del 76,3% y la de insuficiencia cardíaca del 17%. La disfunción ventricular moderada a grave prequirúrgica fue del 23,8% y el 19,8% de las cirugías fueron no programadas. En las cirugías coronarias, el 41,9% de ellas se realizaron sin circulación extracorpórea y se empleó puente mamario en el 89%. El 81,7% de las cirugías mitrales se indicaron por insuficiencia y el 62,6% de las aórticas, por estenosis. En estas cirugías se emplearon válvulas mecánicas en el 58% de los casos. La mediana de internación fue de 6 días. Se presentaron complicaciones mayores en el 31,7% (del 25% en coronarios al 49,36% en combinados) y la mortalidad global fue del 7,7% (del 4,3% en coronarios al 13,4% en combinados). Conclusiones Este registro muestra la realidad de la cirugía cardíaca en centros con residencia o concurrencia de cardiología. Comparadas con cifras de registros nacionales previos, la mortalidad y las complicaciones mayores han disminuido, pero continúan siendo elevadas.

Background The CONAREC and the ESMUCICA studies are the largest multicenter registries performed in Argentina more than 10 years ago. The clinical and surgical advances achieved during the last decade have obliged us to carry out a new national, prospective and multicenter registry to become aware of the characteristics, outcomes, complications and predictors of mortality of patients undergoing cardiac surgery. Objectives To recognize the epidemiologic profile, surgical approach and postoperative outcomes of patients undergoing cardiac surgery in Argentina. Material and Methods This is a prospective, consecutive and multicenter registry performed by residents in Cardiology in 49 centers with cardiovascular surgery facilities. A total of 2553 patients undergoing cardiac surgery were included between September 2007 and October 2008, distributed as follows: coronary artery bypass graft surgery, 1465 patients (57.4%); aortic valve replacement, 359 (14.1%); mitral valve surgery, 169 (6.6%); combined procedure (revascularization-valve surgery), 312 (12.2%); other procedures, 248 (9.7%). Results There were more men (74.9%) than women; mean age was 63±11 years. The prevalence of diabetes was 24.9%, of hypertension 76.3% and of heart failure 17%. Preoperative moderate to severe left ventricular dysfunction was 23.8%, and 19.8% of surgeries were done on an urgent or emergency basis. A 41.9% of coronary artery bypass graft surgeries were done without cardiopulmonary bypass and a mammary artery bypass graft was used in 89%. Mitral valve surgery was indicated due to mitral regurgitation in 81.7% of cases and 63.6% of aortic valve surgeries were due to aortic valve stenosis. Mechanical heart valve prostheses were used in 58% of cases. Patients were hospitalized for a median of 6 days. Major complications occurred in 31.7% of cases (25% in revascularization surgeries and 49.36% in combined procedures) and global mortality was 7.7% (4.3% and 49.36%, respectively). Conclusions This registry demonstrates the real facts in cardiovascular surgery in centers with cardiovascular residents in Cardiology. Mortality and major complications are lower than those reported by previous registers, yet they are still high.