ABSTRACT
Abstract Objectives Refractory angina (RA) is a chronic condition clinically characterized by low effort tolerance; therefore, physical stress testing is not usually requested for these patients. Cardiopulmonary exercise testing (CPET) is considered a gold standard examination for functional capacity evaluation, even in submaximal tests, and it has gained great prominence in detecting ischemia. The authors aimed to determine cardiorespiratory capacity by using the oxygen consumption efficiency slope (OUES) in patients with refractory angina. The authors also studied the O2 pulse response by CPET and the association of ischemic changes with contractile modifications by exercise stress echocardiography (ESE). Methods Thirty-one patients of both sexes, aged 45 to 75 years, with symptomatic (Canadian Cardiovascular Society class II to IV) angina who underwent CPET on a treadmill and exercise stress echocardiography on a lower limb cycle ergometer were studied. ClinicalTrials.gov: NCT03218891. Results The patients had low cardiorespiratory capacity (OUES of 1.74 ± 0.4 L/min; 63.9±14.7% of predicted), and 77% of patients had a flattening or drop in O2 pulse response. There was a direct association between Heart Rate (HR) at the onset of myocardial ischemia detected by ESE and HR at the onset of flattening or drop in oxygen pulse response detected by CPET (R = 0.48; p = 0.019). Conclusion Patients with refractory angina demonstrate low cardiorespiratory capacity. CPET shows good sensitivity for detecting abnormal cardiovascular response in these patients with a significant relationship between flattening O2 pulse response during CEPT and contractile alterations detected by exercise stress echocardiography. Highlights OUES analysis is useful for assessing functional capacity in refractory angina. O2 pulse curve is correlated with contractile alterations in exercise echocardiogram. Cardiopulmonary exercise test is useful toll in patients with refractory angina.
ABSTRACT
FUNDAMENTO: A doença arterial coronariana (DAC) é a principal causa de óbito em pacientes com insuficiência renal crônica (IRC). Os exames não invasivos tradicionais para detecção de DAC e predição de eventos têm apresentado resultados insuficientes nesse grupo. A avaliação do escore de cálcio coronariano (ECC) por tomografia computadorizada tem comprovado valor prognóstico na população sem doença renal. OBJETIVO: Avaliar a acurácia do ECC para detectar DAC obstrutiva e prever eventos cardiovasculares em candidatos a transplante renal comparada à angiografia coronariana invasiva (ACI) quantitativa. MÉTODOS: Foram avaliados 97 pacientes com IRC e idade > 35anos. Foi considerada DAC obstrutiva a presença de estenose >50 por cento ou >70 por cento pela ACI. Dados descritivos, concordância, testes diagnósticos, Kaplan-Meier e análise multivariada foram utilizados. RESULTADOS: O escore de Agatston médio foi de 580,6 ± 1.102,2; os valores mínimos e máximos foram 0 e 7.994, e mediana de 176. Apenas 14 pacientes tinham escore de cálcio de zero. Não houve diferenças entre as etnias e a maior presença de cálcio regional associou-se a maior probabilidade de estenose coronária no mesmo segmento. O escore de cálcio de Agatston apresentou boa acurácia para o diagnóstico de estenose, >50 por cento e >70 por cento com área sob a curva ROC de 0,75 e 0,70, respectivamente. No limiar de 400, o escore de cálcio identificou o subgrupo com maior taxa de eventos cardiovasculares em tempo médio de seguimento de 29,1±11,0 meses. CONCLUSÃO: O ECC na avaliação de DAC apresentou boa performance diagnóstica e prognóstica para eventos cardiovasculares em pacientes com insuficiência renal crônica (IRC).
BACKGROUND: Coronary artery disease (CAD) is the major cause of death among chronic renal failure (CRF) patients. Traditional, non-invasive exams to detect CAD and to predict events have shown insufficient results in this group. CT Scan evaluation of Coronary Calcium Score (CCS) has proven to be of prognostic value for the population reporting no renal condition. OBJECTIVE: To investigate CCS accuracy in detecting obstructive CAD and in predicting cardiovascular events in candidates to renal transplant as compared to quantitative invasive coronary angiography (ICA). METHODS: Ninety-seven (97) CRF patients aged > 35 were evaluated. Obstructive CAD was considered as >50 percent or >70 percent stenosis on ICA. Descriptive data, concordance, diagnostic tests, Kaplan-Meier, and multivariate analysis were used. RESULTS: Agatston mean score was 580.6 ± 1,102.2. Minimum and maximum values were 0 and 7,994, with median at 176. Only 14 patients had zero calcium score. No differences were reported in regard to ethnicity. Highest regional calcium was associated to the highest probability of coronary stenosis in the same segment. Agatston calcium score showed high accuracy for the diagnosis of >50 percent and >70 percent stenosis, with area under ROC curve (AUC) of 0.75 and 0.70, respectively. At the threshold of 400, calcium score identified a subgroup with a higher rate of cardiovascular events at an average follow-up time of 29±11.0 months. CONCLUSION: CCS proved to have good diagnostic and prognostic performance for cardiovascular events evaluation in CRF patients.
FUNDAMENTO: La enfermedad arterial coronaria (EAC) es la principal causa de óbito en pacientes con insuficiencia renal crónica (IRC). Los exámenes no invasivos tradicionales para detección de EAC y predicción de eventos vienen presentando resultados insuficientes en este grupo. La evaluación del score de calcio coronario (SCC) por tomografía computarizada ha estado comprobando valor pronóstico en la población sin enfermedad renal. OBJETIVO: Evaluar la exactitud del SCC para detectar EAC obstructiva y prever eventos cardiovasculares en candidatos a trasplante renal comparada a la angiografía coronaria invasiva (ACI) cuantitativa. MÉTODOS: Se evaluaron a 97 pacientes con IRC y edad > 35 años. Se consideró como EAC obstructiva la presencia de estenosis > 50 por ciento o > 70 por ciento por la ACI. Datos descriptivos, concordancia, pruebas diagnósticas, Kaplan-Meier y análisis multivariado se utilizaron. RESULTADOS: El score de Agatston promedio fue de 580,6 ± 1.102,2; los valores mínimos y máximos fueron 0 y 7.994, y mediana de 176. Solamente 14 pacientes tenían score de calcio de cero. No hubo diferencias entre las etnias y la mayor presencia de calcio regional se asoció a la mayor probabilidad de estenosis coronaria en el mismo segmento. El score de calcio de Agatston presentó buena exactitud para el diagnóstico de estenosis, > 50 por ciento y > 70 por ciento con área bajo la curva ROC de 0,75 y 0,70, respectivamente. En el umbral de 400, el score de calcio identificó el subgrupo con mayor tasa de eventos cardiovasculares en tiempo promedio de seguimiento de 29,1 ± 11,0 meses. CONCLUSIÓN: El SCC en la evaluación de EAC presentó una buena performance diagnóstica y pronostica para eventos cardiovasculares en pacientes con insuficiencia renal crónica (IRC).