Background: Pulmonary hypertension (PH) is commonly associated with heart failure with preserved ejection fraction (HFpEF). In HFpEF, the elevated left sided filling pressures results in isolated post-capillary PH (Ipc-PH) or combined pre- and post-capillary PH (Cpc-PH). Although right heart catheterization (RHC) is the gold standard for diagnosis, it is an invasive test with associated risks. Echocardiogram on the other hand does not help distinguish between Ipc-PH and Cpc-PH. The ability of sub-maximum cardiopulmonary exercise test (CPET) as an adjunct diagnostic tool in PH associated HFpEF is not known. Methods: 46 patients with HFpEF and PH (27 patients with Cpc-PH and 19 patients with Ipc-PH) underwent sub-maximum CPET followed by RHC. The study also included 18 age and gender matched control subjects. Several sub-maximum gas exchange parameters were examined to determine the ability of sub-maximum CPET to distinguish between Ipc-PH and Cpc-PH. Results: Echocardiogram did not distinguish between Ipc-PH and Cpc-PH. Compared to Ipc-PH, Cpc-PH had greater ventilatory equivalent for carbon dioxide (VE/VCO2) slope, reduced delta end-tidal CO2 change during exercise, reduced oxygen uptake efficiency slope (OUES), and reduced gas exchange determined pulmonary vascular capacitance (GXCAP). The latter was significantly associated with RHC determined pulmonary artery compliance (r=0.5; p=0.0004). Conclusion: Sub-maximum gas exchange parameters obtained during CPET in an ambulatory setting allows for discrimination between Ipc-PH and Cpc-PH. Sub-maximum CPET may be a useful end-point measure in HFpEF population.

Right ventricular (RV) functional adaptation to afterload determines outcome in pulmonary hypertension (PH). RV afterload is determined by the dynamic interaction between pulmonary vascular resistance (PVR), characteristic impedance (Zc) and wave reflection. Zc and wave reflection can be estimated from RV pressure waveform analysis and cardiac output. Estimations of Zc and wave reflection coefficient (l) were validated relative to conventional spectral analysis in an animal model. Zc, l, and single beat ratio of end-systolic to arterial elastance (Ees/Ea) to estimate RV-pulmonary arterial (PA) coupling were determined from right heart catheterization (RHC) data. The study included 30 pulmonary artery hypertension (PAH) and 40 heart failure with preserved ejection fraction (HFpEF) patients (20 combined pre- and post-capillary PH; Cpc-PH and 20 isolated post-capillary PH; Ipc-PH). Also included were 10 age and sex-matched controls. There was good agreement with minimal bias between estimated and spectral analysis-derived Zc and l. Zc in PAH and Cpc-PH exceeded that in Ipc-PH and controls. l was increased in Ipc-PH (0.84±0.02), Cpc-PH (0.87±0.05), and PAH (0.85±0.04) compared to controls (0.79±0.03), all p-value<0.05. l was the only afterload parameter associated with RV-PA coupling in PAH. In PH-HFpEF, RV-PA uncoupling was independent of RV afterload. Our findings indicate that Zc and l derived from RV pressure curve, can be used to improve estimation of RV afterload. l is the only afterload measure associated with RV-PA uncoupling in PAH while RV-PA uncoupling in PH-HFpEF appears to be independent of afterload consistent with an inherent abnormality of the RV myocardium.

Functional adaptation of the right ventricle (RV) to its afterload plays an important prognostic role in pulmonary hypertension (PH) [1]. The preferred “multibeat” (MB) method for assessing RV–pulmonary vascular interaction involves the measurement of end-systolic elastance ( E es ), the slope of the end-systolic pressure (ESP) to end-systolic volume over sequential heart beats with varying preload. The E es value is then matched to simultaneous pulmonary arterial (PA) elastance at end systole ( E a ), calculated as ESP pressure divided by stroke volume (SV). The ratio of E es to E a ( E es / E a ) is termed RV–PA coupling, preservation of which indicates maintenance RV functioning in the face of increasing afterload [1]. However, while the MB method is generally regarded as the reference standard, it requires continuous, accurate measurement of RV volume and is therefore not readily applicable in most clinical settings.

Pulmonary hypertension (PH) in interstitial lung disease (ILD) is associated with increased mortality and impaired exertional capacity. Right heart catheterization is the diagnostic standard for PH but is invasive and not readily available. Noninvasive physiologic evaluation may predict PH in ILD. Forty‐four patients with PH and ILD (PH‐ILD) were compared with 22 with ILD alone (non‐PH ILD). Six‐min walk distance (6MWD, 223 ± 131 vs. 331 ± 125 m, p = 0.02) and diffusing capacity for carbon monoxide (DLCO, 33 ± 14% vs. 55 ± 21%, p < 0.001) were lower in patients with PH‐ILD. PH‐ILD patients exhibited a lower gas‐exchange derived pulmonary vascular capacitance (GX CAP , 251 ± 132 vs. 465 ± 282 mL × mmHg, p < 0.0001) and extrapolated maximum oxygen uptake (VO 2max ) (56 ± 32% vs. 84 ± 37%, p = 0.003). Multivariate analysis was performed to determine predictors of VO 2 max . GX CAP was the only variable that predicted extrapolated VO 2 max among PH‐ILD and non‐PH ILD patients. Receiver operating characteristic curve analysis assessed the ability of individual noninvasive variables to distinguish between PH‐ILD and non‐PH ILD patients. GX CAP (area under the curve [AUC] 0.85 ± 0.04, p < 0.0001) and delta ETCO 2 (AUC 0.84 ± 0.04, p < 0.0001) were the strongest predictors of PH‐ILD. A CART analysis selected GX CAP , estimated right ventricular systolic pressure (eRVSP) by echocardiogram, and FVC/DLCO ratio as predictive variables for PH‐ILD. With this analysis, the AUC improved to 0.94 (sensitivity of 0.86 and sensitivity of 0.93). Patients with a GX CAP ≤ 416 mL × mmHg had an 82% probability of PH‐ILD. Patients with GX CAP ≤ 416 mL × mmHg and high FVC/DLCO ratio >1.7 had an 80% probability of PH‐ILD. Patients with GX CAP ≤ 416 mL × mmHg and an elevated eRVSP by echocardiogram >43 mmHg had 100% probability of PH‐ILD. The incorporation of GX CAP with either eRVSP or FVC/DLCO ratio distinguishes between PH‐ILD and non‐PH‐ILD with high probability and may therefore assist in determining the need to proceed with a diagnostic right heart catheterization and potential initiation of pulmonary arterial hypertension‐directed therapy in PH‐ILD patients.

eruption, hypomagnesemia, and osteoporosis with longterm use.The causal relationship between pantoprazole and hyponatremia was assessed using the Naranjo criteria 3 and rated "possible." The syndrome of inappropriate antidiuretic hormone secretion (SIADH) might explain the mechanism of hyponatremia related to pantoprazole.No signs of dehydration, low serum osmolarity, high urine sodium excretion, normal serum potassium, and absence of other causes of hyponatremia were an indication of SIADH. He was also frail and had Parkinson's disease, which are risk factors for SIADH. 4,5 To the best of the knowledge of the authors, this is the first report of hyponatremia induced by pantoprazole in a frail elderly adult. Physicians must be careful when prescribing pantoprazole to elderly adults. Periodic blood sodium monitoring might be recommended, especially in elderly adults who are frail and have Parkinson's disease, which are risk factors for hyponatremia.