Pulmonary Embolism In An Athlete - Mechanism,assessment And Management

Abstract

HISTORY: A 43 year old female, ex- national field hockey player, and physically active presented with sudden onset dyspnoea and left-sided chest pain. PHYSICAL EXAMINATION: The athlete presented at the emergency unit and a routine emergency medical evaluation was performed. Point of care investigations did not reveal any significant abnormalities. She was admitted to ICU for monitoring, further investigation and management. DIFFERENTIAL DIAGNOSES: A myocardial infarction or ischemia or a number of lung pathologies (eg. pulmonary embolus, pulmonary TB, Fibrosis) were considered as differential diagnoses. TESTS AND RESULTS: A CTPA revealed a left lower lobe pulmonary embolus with infarction of the entire lower left lobe. A right to left cardiac shunt was also found. Repeat CTPA performed on day 8 revealed conventional cardiac and great vessel anatomy with no right-to-left shunt and normal left ventricular function. WORKING DIAGNOSES: The athlete is being monitored for chronic thromboembolic pulmonary hypertension, is on anti-coagulation therapy and was cleared to start exercising. She was discharged after 10 days and requested guidance for exercise, 10 weeks post discharge. TREATMENT AND OUTCOMES: A baseline Cardio-pulmonary Exercise Test (CPET) was completed 10 weeks after discharge. Baseline Lung Function Testing and exercise oxygen saturation were normal. Analysis revealed reduced exercise capacity, elevated Ventilation (VE)/Expired CO2 (VCO2) slope, reduced maximal oxygen pulse, reduced breathing reserve, increased maximal breathing frequency and reduced resting PetCO2. Interestingly the slope of the VE/ VCO2 curve indicated a cardiac issue (due to the negative y-axis intercept portrayed on panel 4 of the 9-panel CPET plot. The ECG was unremarkable at rest and with effort.Using the CPET results, a 12-week exercise intervention was developed. The training zone was set at the heart rate where maximum rate of lipid metabolism occurs. A repeat CPET after 6 weeks, showed improvements in skeletal muscle oxygen extraction and exercise capacity. This was indicated by the improved VO2 peak, oxygen uptake efficiency slope (OUES), VT1 % and resting PetCO2).There was also an improvement in pulmonary response to exercise as indicated by the dyspnoea index and breathing index. Yet, the VE/VCO2 slope remained elevated.