Anna Correra

Accuracy and precision of echocardiography versus right heart catheterization for the assessment of pulmonary hypertension

BACKGROUND Echocardiographic studies have contributed to progress in the understanding of the pathophysiology of the pulmonary circulation and have been shown to be useful for screening for and prognostication of pulmonary hypertension, but are considered unreliable for the diagnosis of pulmonary hypertension. We explored this apparent paradox with rigorous Bland and Altman analysis of the accuracy and the precision of measurements collected in a large patient population. METHODS A total of 161 patients referred for a suspicion of pulmonary hypertension were prospectively evaluated by a Doppler echocardiography performed by dedicated cardiologists within 1 h of an indicated right heart catheterization. RESULTS Nine of the patients (6%) were excluded due to an insufficient signal quality. Of the remaining 152 patients, 10 (7%) had no pulmonary hypertension and most others had either pulmonary arterial hypertension (36%) or pulmonary venous hypertension (40%) of variable severities. Mean pulmonary artery pressure, left atrial pressure and cardiac output were nearly identical at echocardiography and catheterization, with no bias and tight confidence intervals, respectively ± 3 mm Hg, ± 5 mm Hg and ± 0.3 L/min. However, the ± 2SD limits of agreement were respectively of + 19 and - 18 mm Hg for mean pulmonary artery pressure, + 8 and - 12 mm Hg for left atrial pressure and + 1.8 and - 1.7 L/min for cardiac output. CONCLUSIONS Doppler echocardiography allows for accurate measurements of the pulmonary circulation, but with moderate precision, which explains why the procedure is valid for population studies but cannot be used for the individual diagnosis of pulmonary hypertension.

Bosentan–sildenafil association in patients with congenital heart disease-related pulmonary arterial hypertension and Eisenmenger physiology

OBJECTIVES The aim of the present study was to evaluate the safety, tolerability, clinical and haemodynamic impact of add-on sildenafil in patients with congenital heart disease (CHD)-related pulmonary arterial hypertension (PAH) and Eisenmenger physiology after failure of oral bosentan therapy. METHODS Thirty-two patients with CHD-related PAH (14 male, mean age 37.1 ± 13.7 years) treated with oral bosentan underwent right heart catheterization (RHC) for clinical worsening. After RHC, all patients received oral sildenafil 20mg thrice daily in addition to bosentan. Clinical status, resting transcutaneous oxygen saturation (SpO(2)), 6-minute walk test (6MWT), serology and RHC were assessed at baseline (before add-on sildenafil) and after 6 months of combination therapy. RESULTS Twelve patients had ventricular septal defect, 8 atrio-ventricular canal, 6 single ventricle, and 6 atrial septal defect. Twenty-eight/32 had Eisenmenger physiology and 4 (all with atrial septal defect) did not. All patients well tolerated combination therapy. After 6 months of therapy, an improvement in clinical status (WHO functional class 2.1 ± 0.4 vs 2.9 ± 0.3; P=0.042), 6-minute walk distance (360 ± 51 vs 293 ± 68 m; P=0.005), SpO(2) at the end of the 6MWT (72 ± 10 vs 63 ± 15%; P=0.047), Borg score (2.9 ± 1.5 vs 4.4 ± 2.3; P=0.036), serology (pro-brain natriuretic peptide 303 ± 366 vs 760 ± 943 pg/ml; P=0.008) and haemodynamics (pulmonary blood flow 3.4 ± 1.0 vs 3.1 ± 1.2l/min/m(2), P=0.002; pulmonary vascular resistances index 19 ± 9 vs 24 ± 16 WU/m(2), P=0.003) was observed. CONCLUSIONS Addition of sildenafil in adult patients with CHD-related PAH and Eisenmenger syndrome after oral bosentan therapy failure is safe and well tolerated at 6-month follow-up, resulting in a significant improvement in clinical status, effort SpO(2), exercise tolerance and haemodynamics.

Therapy for pulmonary arterial hypertension due to congenital heart disease and Down's syndrome

BACKGROUND Oral bosentan is effective in pulmonary arterial hypertension (PAH) related to congenital heart disease (CHD). In patients with Downs syndrome, the effect of bosentan is largely unknown. Aim of the study was to evaluate the long-term effects of bosentan in adult patients with CHD-related PAH with and without Downs syndrome. METHODS WHO functional class, resting oxygen saturation, 6-minute walk test (6 MWT) and hemodynamics were assessed at baseline and after 12 months of bosentan therapy in patients with CHD-related PAH with and without Downs syndrome. RESULTS Seventy-four consecutive patients were enrolled: 18 with and 56 without Downs syndrome. After 12 months of bosentan therapy, both with and without Downs syndrome patients showed an improvement in WHO functional class (Down: 2.5 ± 0.5 vs 2.9 ± 0.6, p=0.005; controls: 2.5 ± 0.5 vs 2.9 ± 0.5, p=0.000002), 6-minute walk distance (Down: 288 ± 71 vs 239 ± 74 m, p=0.0007; controls: 389 ± 80 vs 343 ± 86 m, p=0.00003), and hemodynamics (pulmonary flow, Down: 4.0 ± 1.6 vs 3.5 ± 1.4 l/m/m(2), p=0.006; controls: 3.5 ± 1.4 vs 2.8 ± 1.0 l/m/m(2), p=0.0005; pulmonary to systemic flow ratio, Down: 1.4 ± 0.7 vs 1.0 ± 0.4, p=0.003; controls: 1.1 ± 0.7 vs 0.9 ± 0.3, p=0.012; pulmonary vascular resistance index, Down: 15 ± 9 vs 20 ± 13 WUm(2), p=0.007; controls: 2 0 ± 10 vs 26 ± 15 WUm(2), p=0.002). No differences in the efficacy of therapy were observed between the two groups. CONCLUSIONS Bosentan was safe and well tolerated in adult patients with CHD-related PAH with and without Downs syndrome during 12 months of treatment. Clinical status, exercise tolerance, and pulmonary hemodynamics improved, regardless of the presence of Downs syndrome.

Hemodynamics of patients developing pulmonary arterial hypertension after shunt closure

BACKGROUND Pulmonary arterial hypertension (PAH) after shunt closure is associated with a poor prognosis. The aim of this study was to assess retrospectively the hemodynamics of patients developing PAH after shunt closure. METHODS Hemodynamic data obtained by right heart catheterization (RHC) performed at baseline and after shunt closure were analyzed. RESULTS Twenty-two patients, 13 with atrial septal defect (ASD), 6 with ventricular septal defect (VSD), 1 with patent ductus arteriosus, 1 with both ASD and VSD, and 1 with complete atrio-ventricular canal have been considered. The mean age at closure was 25.3±20.1 years (range of 3 months to 56.7 years), and the mean age at PAH diagnosis was 37.0±20.8 years (range of 5 to 61.2 years). The time delay between shunt closure and PAH diagnosis was 140.2±100.2 months. At baseline RHC, hemodynamic data were as follows: pulmonary vascular resistance (PVR) of 8.6±2.6 Wood units, PVR index (PVRi) of 10.1±2.7 Wood units∗m(2), mean pulmonary arterial pressure of 43.7±9.7 mmHg, PVR to systemic vascular resistance ratio (PVR/SVR) of 0.70±0.23, and Qp/Qs of 1.6±0.4. In particular, 18/22 (81%) had PVR≥5 Wood units, 21/22 (95%) PVRi≥6 Wood units∗m(2), 21/22 (95%) PVR/SVR≥0.33, and 11/22 (50%) Qp/Qs≤1.5. During the follow-up, 5/22 (22%) patients died and one patient underwent successful double lung transplantation. CONCLUSIONS High baseline values of PVR (≥5 Wood units), PVRi (≥6 Wood units∗m(2)) and PVR/SVR (≥0.33) are common findings in patients who develop PAH late after shunt closure. Large prospective clinical trials are needed to establish the safe limits for shunt closure.

Clinical Relevance of Fluid Challenge in Patients Evaluated for Pulmonary Hypertension

Background Fluid challenge may help in the differential diagnosis between pre‐ and postcapillary pulmonary hypertension (PH). However, the test is still in need of standardization and better defined clinical relevance. Methods Two hundred twelve patients referred for PH underwent a right‐sided heart catheterization with measurements before and after rapid infusion of 7 mL/kg of saline. PH was defined as mean pulmonary artery pressure ≥ 25 mm Hg, and postcapillary PH was defined as pulmonary artery wedge pressure (PAWP) > 15 mm Hg. An increase in PAWP ≥ 18 mm Hg was considered diagnostic for postcapillary PH. At baseline, 66 patients received a diagnosis of no PH; 22, of postcapillary PH; and 124, of precapillary PH (mostly pulmonary arterial hypertension). Results After fluid challenge, five of 66 patients with no PH (8%) and eight of 124 with precapillary PH (6%) had the diagnosis reclassified as postcapillary PH. Fluid challenge was associated with an increase in PAWP by 7 ± 2 mm Hg in postcapillary PH and 3 ± 1 mm Hg in both precapillary PH and no‐PH groups. Between‐group differences were significant, but there was overlap. There were no adverse events related to fluid challenge. Prediction bands calculated from quadratic fits of the PAWP responses in pooled control subjects with no PH and patients with precapillary PH helped confirm 18 mm Hg as the cutoff for diagnosing postcapillary PH. Conclusions Fluid challenge with 7 mL/kg saline increases PAWP, more in postcapillary than in precapillary PH or in control subjects with no PH. A cutoff value of 18 mm Hg allows reclassification of 6% to 8% of patients with precapillary PH or normal hemodynamic characteristics at baseline.

Ambrisentan for pulmonary arterial hypertension: long term effects on clinical status, exercise capacity and haemodynamics.

Ambrisentan, an oral endothelin-1-receptor antagonist (ERA) selective for the endothelin A, showed an improvement in WHO functional class, 6 minute walk distance, and time to clinical worsening relative to placebo in randomised, double-blind, placebo-controlled, multicenter, 12-week clinical trials (ARIES study 1 and 2, total n=394) [1]. At this time, the long-term effects of ambrisentan on haemodynamics have not been reported in a prospective study. The aim of this study was to evaluate prospectively the efficacy and safety of ambrisentan treatment in adult patients with pulmonary arterial hypertension by assessing its long term effects on clinical status, exercise capacity, and cardiopulmonary haemodynamics. This was a single-centre, open-label, single-arm, prospective study. All patients with PAH starting oral ambrisentan as first line therapy or combination therapy (based on recommendations of the current ESC/ERS guidelines on pulmonary hypertension) [2] were enrolled after obtaining the informed consent. Clinical status, resting transcutaneous oxygen saturation (SpO2), 6-minute walk distance, serology and right heart catheterization (RHC) were assessed at baseline (before starting ambrisentan therapy) and at 1 year follow-up. The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology [3]. Clinical status evaluation included medical history, assessment of WHO functional class, measurement of systemic arterial pressure, transcutaneous oxygen saturation (SpO2) and heart rate.

FLUID CHALLENGE TEST IN NORMAL SUBJECTS AND IN A HETEROGENEOUS POPULATION WITH PULMONARY HYPERTENSION

Aim of the study was to explore the response to a fluid challenge test (FCT) in normal subjects and in patients with pulmonary hypertension (PH). 168 subjects underwent right heart catheterization in basal conditions and after FCT. At baseline, 50 subjects showed normal pressures (healthy controls