Utility Of Cardiopulmonary Exercise Testing In Chronic Unexplained Dyspnea In A 77 Year Old Female.

HISTORY: A 77-year-old female with 20 year history of dyspnea on exertion (DOE). DOE occurs with 15-25 meters walking on level ground. No associated chest pain, palpitations or presyncope. No history of thrombosis or blood transfusions. She has no relevant family history. No history of miscarriages or rheumatic disease. She denies the use of any anorexigens, tobacco, illicit drugs or other supplements. She has no known hepatic disease. Computerized tomography scan in 2018 showed mi ld dilation of the main pulmonary artery; no evidence of pulmonary embolisms or suspicious lung lesions. PHYSICAL EXAMINATION: In no apparent distress; HEENT: normal; Neck: Neck veins are flat; Respiration: Symmetric excursion. Unlabored. Lung fields clear bilaterally without wheezes or rhonchi; Cardiovascular: Regular rate and rhythm, S1 and S2 without murmur, rub, or gallop. No ectopy; No clubbing, cyanosis or edema. Vitals: Blood Pressure: 121/45 mmHg, Pulse: 78 bpm, Resp: 16/min, Temp: 36.7 °C (98.1 °F), SpO2: 97%. DIFFERENTIAL DIAGNOSIS: Restrictive Lung Disease; Pulmonary Arterial Hypertension; Heart Failure with Preserved Ejection Fraction. TEST AND RESULTS: 6MWT: 411 m, peak BP: 172/55 mmHg, peak HR: 121, SpO2: 97%/97%. Echocardiogram with Doppler: Moderate TR with estimated RVSP = 41 mmHg. RAP = 3 mmHg. Normal RV size and systolic function. Normal LV size and systolic function with estimated LVEF at 67% by MOD. Aortic sclerosis. Mildly thickened mitral valve leaflets. Trace MR/AR/PR. PFTS: Mild restriction (TLC 74%) without obstruction and normal diffusion capacity (94%). CPX: Vo2Max: 18.1 ml/kg/min; Exercise terminated: shortness of breath; RPE: 18/20; RER (0.91) indicates indeterminate exercise challenge; VE/VCO2 slope is 43.8 and VE/VCO2@AT is 39.4, which are both above normal range; Breathing reserve: 10.1%; Oxygen pulse at peak exercise is 8.2 mL/beat, corresponding to 58% of predicted. Exercise ECG response was normal; Peak HR: 136 bpm (93% of predicted); Blood pressure rise was appropriate V/Q scan: Diffuse thromboembolic disease in the lungs. FINAL WORKING DIAGNOSIS: Suspected Chronic Thromboembolic Disease (CTED). TREATMENT AND OUTCOMES: Anticoagulation (apixaban) for 12 weeks (likely long-term). Re-evaluate for residual clotting with V/Q scan. Re-evaluate for need for right-heart catheterization with CPX [ABSTRACT FROM AUTHOR]