Pulmonary artery occlusion pressure may overdiagnose pulmonary artery hypertension in sickle cell disease

Cardiovascular complications of sickle cell disease: A primer for the general clinician

Sickle cell disease (SCD) is the most common hereditary hemoglobinopathy and mainly affects individuals of African ancestry. As survival has improved especially in high-income countries, increased rates of cardiopulmonary complications such as pulmonary hypertension, heart failure with diastolic dysfunction, and sudden death are encountered in clinical practice. These complications are the leading causes of morbidity and mortality as these individuals survive into adulthood. Understanding the need for, early identification, timely intervention, and implementation of preventive strategies are critical in reversing this trend and improving quality of life and survival rates. This manuscript aims to provide a comprehensive review of the pathogenesis of cardiovascular complications associated with sickle cell disease and equip the clinician with tools to facilitate the early diagnosis and management of patients with SCD as increasing numbers survive into adulthood.

Sickle Cell Disease and the Heart.. [DOI: 10.21203/rs.3.rs-3040535/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Purpose The objective of this study was to explore the relationship between cardiac structure, cardiac index (CI), and diastolic function parameters, and laboratory values in patients with Sickle Cell Disease (SCD), and to characterize the distinct SCD cardiomyopathy phenotype Methods We conducted a retrospective review of 202 adult patients with SCD (mean age 41.02 ± 13.36) at our hospital who underwent outpatient echocardiographic screening from 2019–2022. Results Our study identified cardiac hypertrophy, chamber dilatation with preserved ejection fraction, elevated TRV, increased cardiac output, and diastolic dysfunction as defining echocardiographic features in SCD. There was a negative correlation between CI and lateral e’ (R = -0.182, P = 0.012), and a positive correlation between CI and E/e’ (R = 0.274, P = 0.0001). Conclusions Our study identified a unique cardiomyopathy in patients with SCD characterized by cardiac hypertrophy with preserved systolic function, abnormal mitral inflow patterns, and elevated cardiac output. These features are indicative of restrictive physiology, as evidenced by left atrial enlargement and diastolic dysfunction, superimposed on hyperdynamic physiology. Further research is needed to elucidate the pathophysiological mechanisms underlying these observations and determine their prognostic significance in vulnerable populations with an elevated burden of cardiovascular disease, including the risk of sudden cardiac death.

RETROSPECTIVE COMPUTER-ASSISTED IMAGE ANALYSIS OF DOPPLER ECHOCARDIOGRAPHY IN PULMONARY HYPERTENSION PATIENTS

Pulmonary hypertension (PH) is diagnosed invasively by right heart catheterization (RHC), which determines patient’s mean and systolic pulmonary artery pressure (mPAP, sPAP) and pulmonary vascular resistance (PVR). This study sought to identify non-invasive echocardiography parameters useful for screening PH. Patients ([Formula: see text]; 19 normotensive; 17 pre-capillary PH; 48 post-capillary PH) who had undergone transthoracic Doppler echocardiography and RHC within 60 days of each other were identified. Tricuspid regurgitant (TR) jet velocities, velocity spectral densities, average flow rates, and Fourier transforms (FFT) of velocity waveforms were calculated via an in-house MATLAB code. Correlations were found between the FFT magnitude at 0 Hz and sPAP and mPAP for normotensive patients; between the MATLAB-calculated TR jet and sPAP and PVR for all PH patients; and between the sum of FFT magnitudes [Formula: see text][Formula: see text]Hz and mPAP, sPAP, and PVR for post-capillary PH patients. Statistical difference was found between the FFT magnitudes at 2 Hz of pre- and post-capillary PH patients ([Formula: see text]). These results suggest non-invasive parameters with clinical utility for estimating RHC measurements and discriminating between PH types, offering a path forward for less invasive and more accessible PH screening protocol.

Elevated tricuspid regurgitation velocity in congenital hemolytic anemias: Prevalence and laboratory correlates

Elevated tricuspid valve regurgitation jet velocity (TRV ≥ 2.5 m/s) is associated with mortality among adults with sickle cell disease (SCD), but correlative biomarkers are not studied according to treatment exposure or genotypes. To investigate the associations between biomarkers and TRV elevation, we examined the relationship between TRV and hemolytic, inflammatory, and cardiac biomarkers, stratified by disease-modifying treatments and SCD genotype. In total, 294 participants with SCD (mean age, 11.0 ± 3.7 years) and 49 hereditary spherocytosis (HS; mean age, 22.9 ± 19.75 years) were included for comparison and enrolled. TRV was elevated in 30.7% of children with SCD overall: 18.8% in HbSC/HbSβ⁺ -thalassemia, 28.9% in untreated HbSS/HbSβ⁰ -thalassemia, 34.2% in HbSS/HbSβ⁰ -thalassemia hydroxyurea-treated, and 57% in HbSS/HbSβ⁰ -thalassemia chronic transfusion treated. TRV was elevated in 10.7% and 27.8% in HS children and adults, respectively. In children with SCD, elevated TRV was correlated with hemoglobin (odds ratio [OR] = 0.78, P = 0.004), lactate dehydrogenase (LDH; OR = 2.52, P = 0.005), and N-terminal pro-brain natriuretic peptide (NT-pro BNP; OR = 1.003, P = 0.004). In multivariable logistic regression, adjusting for genotype, sex, hemolytic index, and treatment, hemoglobin concentration remained the only significant variable associated with elevated TRV in untreated HbSS/HbSβ⁰ -thalassemia participants. TRV was not associated with inflammatory markers, other markers of hemolysis, or NT-pro BNP in untreated HbSS/HbSβ⁰ -thalassemia. Neither hemoglobin nor LDH was associated with TRV in HbSC/HbSβ⁺ -thalassemia. These results suggest that elevated TRV is influenced by the degree of anemia, possibly reflecting sickling as part of the disease pathophysiology. Prospective studies should monitor hemoglobin concentration as children with SCD age into adulthood, prompting initiation of TRV screening and monitoring.

Cardiovascular manifestations of sickle cell disease

Sickle cell disease (SCD) is the most frequent genetic haemoglobinopathy worldwide. Early childhood mortality has dramatically decreased in high-income countries, and most patients now survive beyond the 5th decade. However, in the aging SCD population, the morbidity related to chronic organ damage, especially kidney and heart, has become a major concern. While pulmonary hypertension has attracted most attention, it appears that this condition is frequently linked to left heart failure (HF). Accordingly, SCD-associated cardiomyopathy is emerging as a major cause of reduced quality of life and early mortality in these patients. The diagnosis of this particular phenotype of high-output HF is challenging. Exercise intolerance and dyspnoea in SCD patients are linked to multiple causes including chronic anaemia. Moreover, echocardiographic features are unusual and can be misinterpreted. The classical diagnosis algorithm for HF is generally not suitable in SCD patients, and HF is poorly recognized and mostly diagnosed at a late congestive stage in routine practice. Such patients need to be identified at an earlier stage of myocardial dysfunction via improved phenotyping. This constitutes the first step towards further investigations in SCD needed to improve the prognosis and the quality of life. This article provides an updated review of the recent advances in the pathophysiology and diagnosis, and in addition, perspectives of new therapeutic approaches in SCD-related cardiac manifestations.

The global burden of pulmonary hypertension in sickle cell disease: a systematic review and meta-analysis

Elevated tricuspid regurgitant jet velocity (TRJV) is a surrogate measure of pulmonary hypertension (PH) in persons with sickle cell disease (SCD). We sought to estimate the burden of PH in people living with sickle cell disease based on TRJV. From 2000 to 2015, we searched electronic databases for eligible publications and included 29 studies (n = 5358 persons). We used random effects modeling to determine the pooled estimate of elevated TRJV. The overall pooled prevalence of elevated TRJV was 23.5 %(95 % CI 19.5-27.4) in persons with SCD. The pooled prevalence of elevated TRJV in children and adults with SCD was 20.7 % (95 % CI 15.7--25.6) and 24.4 % (95 % CI 18.4-30.4), respectively. TRJV is prevalent among adults and children with SCD. Our finding support international recommendations that call for screening for PH in SCD patients.

Cardiomyopathy With Restrictive Physiology in Sickle Cell Disease

OBJECTIVES

The aim of this study was to identify a unifying cardiac pathophysiology that explains the cardiac pathological features in sickle cell disease (SCD).

BACKGROUND

Cardiopulmonary complications, the leading cause of adult death in SCD, are associated with heart chamber dilation, diastolic dysfunction, elevated tricuspid regurgitant jet velocity (TRV), and pulmonary hypertension. However, no unifying cardiac pathophysiology has been identified to explain these findings.

METHODS

In a 2-part study, we first examined patients with SCD who underwent screening echocardiography during steady state at our institution. We then conducted a meta-analysis of cardiac studies in SCD.

RESULTS

In the 134 patients with SCD studied (median age 11 years), significant enlargement of the left atrial volume was present (z-score 3.1, p = 0.002), shortening fraction was normal (37.6 ± 4.7%), and lateral and septal ratios of mitral velocity to early diastolic velocity of the mitral annulus (E/e') were severely abnormal in 8% and 14% of patients, respectively, indicating impaired diastolic function. Both TRV and lateral E/e' correlated with enlarged left atrial volume in SCD (p = 0.003 and p = 0.006, respectively). Meta-analysis of 68 studies confirmed significant left atrial diameter enlargement in patients with SCD compared with controls, evidence of diastolic dysfunction and enlarged left ventricular end-diastolic dimension with normal shortening fraction. The majority of patients with catheter-confirmed pulmonary hypertension had mild pulmonary venous hypertension consistent with restrictive cardiac physiology.

CONCLUSIONS

Patients with SCD have a unique form of cardiomyopathy with restrictive physiology that is superimposed on hyperdynamic physiology and is characterized by diastolic dysfunction, left atrial dilation, and normal systolic function. This combination results in mild, secondary, pulmonary venous hypertension and elevated TRV. Sudden death is common in other forms of restrictive cardiomyopathy. Our finding of this unique restrictive cardiomyopathy may explain the increased mortality rates and sudden death seen in patients with SCD with mildly elevated TRV.

Pulmonary hypertension in sickle cell disease: diagnosis and management

The increased survival of patients with sickle cell disease (SCD) into adulthood is associated with an increased incidence of multiorgan dysfunction and a progressive systemic and pulmonary vasculopathy. The high prevalence of an elevated tricuspid regurgitant jet velocity and its association with an increased risk of death in adult patients is well established. However, there has been controversy regarding the prevalence of pulmonary hypertension (PH) and its association with mortality in SCD. Multiple recently published reports demonstrate that PH as diagnosed by right heart catheterization is common in adult SCD patients, with a prevalence of 6%–11%. Furthermore, PH is associated with an increased risk of death in SCD patients. In this chapter, we provide evidence for the high prevalence of PH in SCD and its association with mortality and make recommendations for its evaluation and management. Finally, we provide the rationale for screening for this life-threatening complication in adult patients with SCD.