Atorvastatin treatment improves myocardial and peripheral blood flow in familial hypercholesterolemia subjects without evidence of coronary atherosclerosis.

BACKGROUND: Hypercholesterolemia induces early microcirculatory functional and structural alterations that are reversible by cholesterol reduction. Real time myocardial contrast echocardiography (RTMCE) and vascular ultrasound evaluate the effects of hyperlipidemia on peripheral and central blood flow reserve. This study investigated the effects of lipid-lowering therapy on coronary and peripheral artery circulation in patients with familial hypercholesterolemia (FH). METHODS: RTMCE and vascular ultrasound were performed in 10 healthy volunteers (validation group) at baseline and after 12-week clinical observation, and in 16 age- and sex-matched FH patients without obstructive coronary artery disease (CAD) by computed tomography angiography at baseline and after 12-week atorvastatin treatment. Indexes of relative myocardial blood flow (MBF) were obtained at rest and during adenosine infusion. RESULTS: In validation group, there was no significant difference between flow-mediated dilation (FMD) at baseline and after 12 weeks (0.15 ± 0.02 vs. 0.14 ± 0.03; P = 0.39). Similarly, no differences were observed in MBF reserve at baseline and after 12 weeks (3.31 ± 0.63 vs. 3.48 ± 0.89; P = 0.89). FMD was blunted in FH patients, at baseline, as compared with validation group (0.08 ± 0.04 vs. 0.15 ± 0.02; P < 0.001) and became similar to that group (0.13 ± 0.05 vs. 0.14 ± 0.03; P = 0.07) after treatment. MBF reserve was blunted at baseline in FH patients in comparison with the validation group (2.78 ± 0.71 vs. 3.31 ± 0.63; P = 0.003). After treatment, MBF reserve values were no longer different (3.43 ± 0.66 and 3.48 ± 0.89; P = 0.84, respectively, for FH and validation groups). CONCLUSION: Patients with FH and no obstructive CAD have blunted MBF reserve and lower FMD values as compared with healthy volunteers. Both FMD and MBF reserve were normalized after atorvastatin treatment.

Segurança e eficácia da infusão precoce de atropina durante a ecocardiografia sob estresse pela dobutamina - um estudo comparativo com o protocolo convencional / Safety and efficacy of the early injection of atropine during dobutamines stress echocardiography - a comparative estudy with the conventional protocol

RESUMO: Objetivo: Determinar a segurança, eficácia, e acurácia diagnóstica da infusão precoce de atropina durante a ecocardiografia sob estresse peladobutamina (AP-EED), em comparação com o protocolo convencional de dobutamina-atropina (EEDA), em pacientes com doença arterial coronariana (DAC) conhecida ou suspeita. Introdução: Embora a EEDA seja um método bem estabelecido para avaliar pacientes com DAC, pode resultar em longa duração do teste e exposição dos pacientes a altas doses de dobutamina. Novos protocolos, incluindo AP-EED, têm sido propostos para reduzir aduração do teste. Métodos: Estudamos retrospectivamente 3163 pacientes submetidos a EEDA e 1664 pacientes submetidos a AP-EED, em um período de 12 anos. No protocolo EEDA, atropina foi injetada apenas na dose máxima de dobutamina, enquanto na AP-EED atropina foi iniciada com 20mcg/Kg/min de dobutamina se a freqüência cardíaca estivesse <100 bpm, até 2mg. A acurácia diagnóstica para detecção de DAC (estenose >50 por cento em >_1 artéria coronariana) foi avaliada em pacientes que realizaram angiografia quantitativa dentro de três meses após o ecocardiograma sob estresse. Resultados: A dose total de dobutamina utilizada na AP-EED foi menor que na EEDA (31+- 6 verso 36 +- 6 mcg/Kg/min;p<0,OOO1), enquanto a dose de atropina foi maior (0,8+-0,5 verso 0,5+-0,25 mg; p<0,0001). Com AP-EED houve redução significativa da duração do teste (12,4+-2,0 verso 14,6+-2,5 minutos;p<0,OO01), maior porcentagem de testes eficazes (88 por cento verso 81 por cento;p