Importance of End-Diastolic Rather than End-Systolic Right Atrial Size in Chronic Pulmonary Hypertension.

BACKGROUND: Right atrial (RA) enlargement has been associated with worse clinical outcomes in chronic pulmonary hypertension (cPH) patients. Even though current guidelines only recommend measurement of RA dimensions at the end of ventricular systole in these patients, there is paucity of information regarding the potential utility of RA dimensions obtained at the end of ventricular diastole. METHODS: In this retrospective study, standard echocardiographic data were collected from 80 studies. The population studied was divided into Group I that consisted of 35 patients (52 ± 10 years) without PH while Group II included 45 patients (56 ± 14 years; P = 0.2) with cPH. RA measurements were obtained not only at the end of ventricular systole, but also at the end of ventricular diastole to determine which RA measurement was more indicative of abnormal right ventricular afterload. RESULTS: Even though all RA measurements were abnormal, RA area (>8.4 cm(2) ) measured at the end of ventricular diastole was the most useful RA variable to identify cPH patients with elevated pulmonary pressures (P < 0.0001) and with an abnormal pulmonary vascular resistance (P = 0.001). CONCLUSIONS: Based on these results, it appears that isolated RA measurements made at the end of ventricular systole are insufficient to fully explain the hemodynamic load of cPH. Additional studies are now required to determine whether sequential monitoring of the composite change in RA dimensions that occur throughout the cardiac cycle over time correlates better with response to vasodilator therapy and overall clinical outcomes.

Worsening gradient of aortic stenosis with treatment of pulmonary arterial hypertension in scleroderma.

Systemic sclerosis (SSc) can cause interstitial lung and pulmonary vascular disease that can induce pulmonary arterial hypertension (PAH). It is well known that severe PAH may reduce left ventricluar preload and decrease diastolic filling with the potential of reducing forward flow. We present a case in which a patient with SSc and symptomatic PAH required direct pulmonary vasodilator therapy for treatment of elevated pulmonary pressures. On follow-up echocardiogram, while improvement in right ventricular function and reduction in estimated pulmonary pressures were noted; worsening of aortic valve gradients was also found. Cardiac hemodynamics of pulmonary vasodilator therapy is discussed and the literature is reviewed.

Objective measures of right ventricular function during exercise: results of a pilot study.

BACKGROUND: A growing body of evidence seems to suggest that reduction in right ventricular (RV) systolic function is not only associated with both development of symptoms associated with pulmonary arterial hypertension (PAH) but also increased morbidity and adverse clinical outcomes. Recent data suggest that supine bicycle stress echocardiography (sBEE) is feasible and provides realistic resistance and compliance estimations. METHODS: The study design was a retrospective analysis of sBEE obtained for clinical indications of dyspnea on exertion or unexplained exercise intolerance. A total of 30 sBEE studies were included. The first 10 sBEE studies served as a calibration cohort not only to establish objective measures of RV performance but also to determine feasibility and reproducibility. The following 20 sBEE served as a validation cohort. RESULTS: Our results demonstrate that tricuspid annular plane systolic excursion and tricuspid annular systolic velocity, even when measured by an untrained reader, are reliable and accurate measures of the RV response to exercise during a sBEE protocol. Furthermore, measurements of RV myocardial performance (Tei index) or peak RV strain during exercise not only are time consuming but also simply unreliable and should not be utilized to evaluate RV function during sBEE. CONCLUSION: The results of our pilot study suggest that sBEE might be promising for detecting RV abnormalities during exercise. A larger prospective study is now needed to determine if TAPSE and tricuspid annular systolic velocity recorded during sBEE might be useful in assessing patients presenting with dyspnea during exercise or suspected of having PAH.

Right ventricular ejection efficiency: a new echocardiographic measure of mechanical performance in chronic pulmonary hypertension.

BACKGROUND: The severity of pulmonary vascular resistance (PVR) is known to be a critical determinant of right ventricular (RV) systolic function; this relationship remains poorly characterized. We therefore, designed a study to examine the relationship that exists between echocardiographically measured PVR and maximal tricuspid annular plane systolic excursion (TAPSE) to gain some insight regarding RV ejection efficiency (RVEe) in patients with chronic pulmonary hypertension (cPH). METHODS: Standard echocardiographic measures of RV size and systolic performance were recorded from 95 patients (age 54 ± 15 years and pulmonary artery systolic pressures [PASP] that range from 20 to 125 mmHg). For this study, RVEe was defined as TAPSE/Echocardiographic PVR. RESULTS: A strong negative correlation (R(2) = -0.51, P < 0.001) was seen between TAPSE and PASP; however, a power curve trend line fit the relationship between RVEe and PASP (R(2) = 0.77; P < 0.01). In a multiple regression analysis, abnormal pulmonary pressures were better identified when RVEe (P < 0.0001) was used. CONCLUSIONS: Based on these results, it appears that measurement of RVEe might be extremely useful for the assessment of RV mechanics and plasticity. The power curve relationship clearly demonstrates that minimal changes in PASP (up to 50 mmHg) result in dramatic reductions in RVEe. A steady decline in RVEe, though at a lower rate, continues to occur with increasing PASP. Additional studies are required using RVEe into a functional RV imaging algorithm and determine if RVEe correlates with development of symptoms, response to therapy and overall clinical outcomes.