Obesity paradox in pulmonary hypertension due to left ventricular systolic dysfunction

OBJECTIVE

Pulmonary hypertension (PH) due to left ventricular systolic dysfunction (PH-HFrEF) is a common heart disease with poor prognosis. In this study, we explored the risk factors for PH-HFrEF and investigated the related factors affecting the prognosis of PH-HFrEF patients.

METHODS

The study recruited consecutive patients with PH-HFrEF and systolic pulmonary artery pressure (sPAP) of more than 40 mm Hg with left ventricular ejection fraction (LVEF) of less than 45% on echocardiography. Patients with left ventricular systolic dysfunction (HFrEF) but without PH (sPAP < 30 mmHg and LVEF < 45%) were chosen as the control group. Patients were followed up for 18 months, and major adverse cardiac events (MACE) were recorded.

RESULTS

In total, 93 patients with PH-HFrEF formed the study group and 93 LVEF-matched patients with HFrEF were enrolled as controls. Body mass index (BMI) in PH-HFrEF patients was significantly lower compared with the control group (p < 0.05). Multivariate logistic regression analysis revealed that low BMI was an independent predictor of the presence of PH in patients with HFrEF (p < 0.05). There were 23 (24.7%) MACE in the PH-HFrEF group and 18 (19.4%) MACE in the control group. Cox regression analysis showed that low BMI was an independent predictor of MACE occurrence in the PH-HFrEF group (p < 0.05).

CONCLUSION

Low BMI appear to be significantly associated with PH occurrence in patients with HFrEF, and is an independent predictor of MACE in patients with PH-HFrEF.

Levosimendan reduces segmental pulmonary vascular resistance in isolated perfused rat lungs and relaxes human pulmonary vessels

INTRODUCTION

Levosimendan is approved for acute heart failure. Within this context, pulmonary hypertension represents a frequent co-morbidity. Hence, the effects of levosimendan on segmental pulmonary vascular resistance (PVR) are relevant. So far, this issue has been not studied. Beyond that the relaxant effects of levosimendan in human pulmonary vessel are unknown. We addressed these topics in rats' isolated perfused lungs (IPL) and human precision-cut lung slices (PCLS).

MATERIAL AND METHODS

In IPL, levosimendan (10 μM) was perfused in untreated and endothelin-1 pre-contracted lungs. The pulmonary arterial pressure (PPA) was continuously recorded and the capillary pressure (Pcap) was determined by the double-occlusion method. Thereafter, segmental PVR, expressed as precapillary (Rpre) and postcapillary resistance (Rpost) and PVR were calculated. Human PCLS were prepared from patients undergoing lobectomy. Levosimendan-induced relaxation was studied in naïve and endothelin-1 pre-contracted PAs and PVs. In endothelin-1 pre-contracted PAs, the role of K+-channels was studied by inhibition of KATP-channels (glibenclamide), BKCa2+-channels (iberiotoxin) and Kv-channels (4-aminopyridine). All changes of the vascular tone were measured by videomicroscopy. In addition, the increase of cAMP/GMP due to levosimendan was measured by ELISA.

RESULTS

Levosimendan did not relax untreated lungs or naïve PAs and PVs. In IPL, levosimendan attenuated the endothelin-1 induced increase of PPA, PVR, Rpre and Rpost. In human PCLS, levosimendan relaxed pre-contracted PAs or PVs to 137% or 127%, respectively. In pre-contracted PAs, the relaxant effect of levosimendan was reduced, if KATP- and Kv-channels were inhibited. Further, levosimendan increased cGMP in PAs/PVs, but cAMP only in PVs.

DISCUSSION

Levosimendan reduces rats' segmental PVR and relaxes human PAs or PVs, if the pulmonary vascular tone is enhanced by endothelin-1. Regarding levosimendan-induced relaxation, the activation of KATP- and Kv-channels is of impact, as well as the formation of cAMP and cGMP. In conclusion, our results suggest that levosimendan improves pulmonary haemodynamics, if PVR is increased as it is the case in pulmonary hypertension.

Effect of beraprost on pulmonary hypertension due to left ventricular systolic dysfunction

Beraprost is used to treat peripheral chronic arterial occlusive disease. However, the efficacy and safety of beraprost in patients with pulmonary hypertension (PH) due to left ventricular systolic dysfunction (PH-HFrEF) remains unknown. The primary objective of this study was to determine the effects of beraprost on PH-HFrEF.We prospectively recruited patients with PH-HFrEF as determined by echocardiography and right cardiac catheterization. Beraprost sodium was given orally (1 μg/kg/d) added to the usual treatment, and patients were evaluated at 1-year follow-up.Twenty-five patients were recruited with baseline systolic pulmonary artery pressure (PAP) of 49.5 ± 10.8 mm Hg. Systolic PAP results at 3, 6, 9, and 12 months were 39.1 ± 8.1, 30.4 ± 5.2, 27.7 ± 3.0, and 27.0 ± 4.7 mm Hg, respectively, which were all significantly lower than systolic PAP at baseline (P < .05). Left ventricular ejection fraction results at 6 months (43.5 ± 7.0%), 9 months (47.0 ± 5.5%), and 12 months (48.2 ± 4.8%) were significantly higher than at baseline (34.7 ± 9.2%) (P < .05). Six-minute walking distance at 3 months (282.8 ± 80.6 m), 6 months (367.1 ± 81.2 m), 9 months (389.8 ± 87.1 m), and 12 months (395.7 ± 83.4 m) increased with time, and all were significantly higher than baseline (190.1 ± 75.5 m) (P < .05). One patient developed atrial fibrillation and recovered to sinus rhythm after intravenous administration of amiodarone. There were no instances of cardiac-related death, severe bleeding, or severe impairment of liver function.Routine oral administration of beraprost sodium added to the usual treatment may improve cardiopulmonary hemodynamics and exercise capacityin patients with PH-HFrEF.

Exercise-induced pulmonary hypertension by stress echocardiography: Prevalence and correlation with right heart hemodynamics

OBJECTIVES

The aim of this study was to determine the prevalence of exercise-induced pulmonary hypertension (EIPH) in consecutive subjects referred for stress echocardiography for chest pain or shortness of breath and correlate echocardiographic diagnosis of EIPH with hemodynamics at right heart catheterization (RHC).

BACKGROUND

Elevated pulmonary pressure can lead to significant morbidity and mortality. EIPH by ehocardiography has been described in patients with connective tissue disease. It's prevalence in the setting of routine clinically indicated stress echocardiography unknown.

METHODS

In a retrospective analysis of 4068 consecutive stress subjects undergoing stress echocardiography, 479 subjects with EIPH were identified. All 479 subjects with EIPH were compared to 479 age and sex matched subjects with normal pulmonary artery pressures post exercise. EIPH was defined as PASP>50mmHg or peak tricuspid regurgitation velocity>3.2m/s. Of 100 patients with EIPH who underwent RHC we identified variables which predicted abnormal hemodynamic findings on RHC.

RESULTS

The prevalence of EIPH in subjects referred for stress echocardiography was 11.7%. A greater proportion of subjects with EIPH were obese or had lung disease or connective tissue disease. Of 100 subjects who underwent RHC, 65 had abnormal results. Age>55years (OR 5.1, p<0.01]) or dilated left atrium (OR 4.4, p=0.02]) were independently associated with abnormal right heart hemodynamics.

CONCLUSIONS

The results demonstrate that 11.7% of patients undergoing clinically indicated stress echocardiography have EIPH. Of those who underwent RHC abnormal hemodynamics were significantly associated with a dilated left atrium or age older than 55years.

Under pressure: pulmonary hypertension associated with left heart disease

Pulmonary hypertension (PH) associated with left heart disease (PH-LHD) is the most common type of PH, but its natural history is not well understood. PH-LHD is diagnosed by right heart catheterisation with a mean pulmonary arterial pressure ≥25 mmHg and a pulmonary capillary wedge pressure >15 mmHg. The primary causes of PH-LHD are left ventricular dysfunction of systolic and diastolic origin, and valvular disease. Prognosis is poor and survival rates are low. Limited progress has been made towards specific therapies for PH-LHD, and management focuses on addressing the underlying cause of the disease with supportive therapies, surgery and pharmacological treatments. Clinical trials of therapies for pulmonary arterial hypertension in patients with PH-LHD have thus far been limited and have provided disappointing or conflicting results. Robust, long-term clinical studies in appropriate target populations have the potential to improve the outlook for patients with PH-LHD. Herein, we discuss the knowledge gaps in our understanding of PH-LHD, and describe the current unmet needs and challenges that are faced by clinicians when identifying and managing patients with this disease.

Pulmonary hypertension due to left heart disease is associated with multiple unmet medical needshttp://ow.ly/TFET8

Left ventricular dysfunction in patients with suspected pulmonary arterial hypertension

OBJECTIVE:

To evaluate the role of right heart catheterization in the diagnosis of pulmonary arterial hypertension (PAH).

METHODS:

We evaluated clinical, functional, and hemodynamic data from all patients who underwent right heart catheterization because of diagnostic suspicion of PAH-in the absence of severe left ventricular dysfunction (LVD), significant changes in pulmonary function tests, and ventilation/perfusion lung scintigraphy findings consistent with chronic pulmonary thromboembolism-between 2008 and 2013 at our facility.

RESULTS:

During the study period, 384 patients underwent diagnostic cardiac catheterization at our facility. Pulmonary hypertension (PH) was confirmed in 302 patients (78.6%). The mean age of those patients was 48.7 years. The patients without PH showed better hemodynamic profiles and lower levels of B-type natriuretic peptide. Nevertheless, 13.8% of the patients without PH were categorized as New York Heart Association functional class III or IV. Of the 218 patients who met the inclusion criteria, 40 (18.3%) and 178 (81.7%) were diagnosed with PH associated with LVD (PH-LVD) and with PAH, respectively. The patients in the HP-LVD group were significantly older than were those in the PAH group (p < 0.0001).

CONCLUSIONS:

The proportional difference between the PAH and PH-LVD groups was quite significant, considering the absence of echocardiographic signs suggestive of severe LVD during the pre-catheterization investigation. Our results highlight the fundamental role of cardiac catheterization in the diagnosis of PAH, especially in older patients, in whom the prevalence of LVD that has gone undiagnosed by non-invasive tests is particularly relevant.