RESUMO
OBJECTIVES: To evaluate the prognostic value of transit time (TT) assessment in the systemic circulation and organ perfusion in patients with ventricular dysfunction (VD). The primary endpoint was defined as death, heart failure admission, or ventricular arrhythmias, and the secondary endpoint was worsening renal function. METHODS: A retrospective study on 139 patients who underwent cardiac magnetic resonance for VD evaluation and 50 controls. TT was measured as peak-to-peak time in signal intensity over time curves obtained at different stages of circulation (right cavities, left cavities, aorta, and peripheral organs) from first-pass perfusion images. Outcomes were monitored over a median follow-up of 15 months. RESULTS: A total of 139 patients were included (84% male, age 63 [57-70] years). Patients exhibited significantly prolonged TT compared to controls, with in-patients showing longer times than outpatients. Among the 29 patients reaching the primary endpoint, both PTT and STT were significantly prolonged (PTT: 9.75 s vs 13.4 s, p < 0.01; STT: 4.77 s vs 7.00 s, p < 0.01). Concurrent prolongation of PTT (> 10 s) and STT (> 5 s) was associated with a higher event probability (42.3%), compared to isolated abnormalities (6.3% for PTT, 6.7% for STT). Multivariate analysis revealed that combined PTT and STT alteration independently predicted the combined endpoint (HR IC 95%: 8.685 (2.415-31.236), p = 0.001). Prolonged RPT was independently associated with renal function deterioration (OR IC 95%: 1.129 (1.015-1.256), p = 0.024). CONCLUSIONS: Evaluation of TT beyond pulmonary circulation provides prognostic insights into VD. Simultaneous assessment of PTT and STT enhances specificity compared to isolated PTT evaluation, predicting combined adverse events. RPT is independently associated with renal impairment. CLINICAL RELEVANCE STATEMENT: For the first time, it is described that transit time can be evaluated in systemic circulation and in peripheral organs and that this assessment can be easily made from conventional CMR perfusion images and holds significant prognostic value. KEY POINTS: Pulmonary transit time is a valuable hemodynamic parameter; systemic transit time may also be valuable. Transit time can be measured in the systemic circulation, and is longer in patients with ventricular dysfunction. Systemic transit time assessed by magnetic resonance imaging identifies patients with ventricular dysfunction who will experience events during follow-up.
RESUMO
Durante los últimos años, se ha observado la asociación del supradesnivel de ST en la derivación aVR con el compromiso de la arteria descendente anterior (DA), tronco coronario izquierdo (TCI) y coronaria derecha (CD), en el contexto de un infarto de miocardio agudo con segmento ST elevado (IMA-STE). Por medio del electrocardiograma se puede predecir con una probabilidad del 80% el compromiso de TCI frente a DA, cuando la relación aVR sobre V1 es mayor a la unidad. Asimismo, la presencia de un supradesnivel en aVR se asocia a mayor mortalidad a los 30 dias en IMA-STE de cara anterior e inferior. Por lo expuesto previamente, se recalca la importancia del análisis de la elevación del ST en aVR en un IMA-STE de cara anterior puesto que predice compromiso de gran territorio vascular y empeora el pronóstico del paciente.
During last years an association between elevation of the ST segment in the aVR derivation with the affection of the anterior descending coronary artery (ADCA), left coronary artery trunk (LCT) and right coronary artery (RCA) in the context of acute myocardial infarction with elevated ST segment (AMI-ESS) has been observed. The electrocardiogram may predict with 80% accuracy the affection of the LCT versus ADCA when the relation of aVR over V1 in higher than 1. Moreover, an elevation of the ST segment in aVR is associated with higher 30- day mortality in patients with AMI-ESS of the anterior and inferior side. Therefore, we emphasize the importance of analyzing the elevation of the ST segment in aVR in patients with AMI-ESS of the anterior side as it predicts extensive vascular affection and worsens prognosis.