M. Groenink

Right Ventricular Failure Following Chronic Pressure Overload Is Associated With Reduction in Left Ventricular Mass : Evidence for Atrophic Remodeling

OBJECTIVESnWe sought to study whether patients with right ventricular failure (RVF) secondary to chronic thromboembolic pulmonary hypertension (CTEPH) have reduced left ventricular (LV) mass, and whether LV mass reduction is caused by atrophy.nnnBACKGROUNDnThe LV in patients with CTEPH is underfilled (unloaded). LV unloading may cause atrophic remodeling that is associated with diastolic and systolic dysfunction.nnnMETHODSnWe studied LV mass using cardiac magnetic resonance imaging (MRI) in 36 consecutive CTEPH patients (before/after pulmonary endarterectomy [PEA]) and 11 healthy volunteers selected to match age and sex of patients. We studied whether LV atrophy is present in monocrotaline (MCT)-injected rats with RVF or controls by measuring myocyte dimensions and performing in situ hybridization.nnnRESULTSnAt baseline, CTEPH patients with RVF had significantly lower LV free wall mass indexes than patients without RVF (35 ± 6 g/m(2) vs. 44 ± 7 g/m(2), p = 0.007) or volunteers (42 ± 6 g/m(2), p = 0.006). After PEA, LV free wall mass index increased (from 38 ± 6 g/m(2) to 44 ± 9 g/m(2), p = 0.001), as right ventricular (RV) ejection fraction improved (from 31 ± 8% to 56 ± 12%, p < 0.001). Compared with controls, rats with RVF had reduced LV free wall mass and smaller LV free wall myocytes. Expression of atrial natriuretic peptide was higher, whereas that of α-myosin heavy chain and sarcoplasmic reticulum calcium ATPase-2 were lower in RVF than in controls, both in RV and LV.nnnCONCLUSIONSnRVF in patients with CTEPH is associated with reversible reduction in LV free wall mass. In a rat model of RVF, myocyte shrinkage due to atrophic remodeling contributed to reduction in LV free wall mass.

Latest insights in therapeutic options for systemic right ventricular failure: a comparison with left ventricular failure.

The number of adult patients with a systemic right ventricle (RV) is steadily increasing. Survival is relatively good in these patients, but deterioration of the systemic RV seems inevitable. Although therapeutic options for patients with LV failure are well established, their role in patients with systemic RV failure is often undefined. To appreciate the potency of LV failure therapy in patients with a systemic RV, insight into pathophysiology of systemic RV failure and into recent developments in therapeutic research are indispensible. This review provides these insights, and will facilitate and ameliorate therapeutic decision making in patients with a systemic RV.

Critical appraisal of the revised Ghent criteria for diagnosis of Marfan syndrome

Radonic T, de Witte P, Groenink M, de Bruin‐Bon RACM, Timmermans J, Scholte AJH, van den Berg MP, Baars MJH, van Tintelen JP, Kempers M, Zwinderman AH, Mulder BJM. Critical appraisal of the revised Ghent criteria for diagnosis of Marfan syndrome.

Right ventricular function in congenital cardiac disease: noninvasive quantitative parameters for clinical follow-up

Right ventricular function is of great importance in patients with both acute and chronic ventricular overload. The early detection of right ventricular dysfunction may have an impact on therapeutic decision making, helping to prevent or further delay functional deterioration of the right ventricle. In patients with right ventricular overload due to congenital cardiac diseases, dobutamine stress testing combined with magnetic resonance imaging, electrocardiographic changes, and monitoring of concentrations of plasma brain natriuretic peptide are very suitable parameters for the early detection of ventricular dysfunction, and should therefore be used in the follow-up of these patients. It is apparent that no single measurement of anatomy or function can ever adequately describe the form or performance of the right ventricle. Rather, we should be looking more towards an integrated approach of different parameters for right ventricular function. The quantitative parameters described in this study can serve this purpose. The strong correlation found between these non-invasive and independent parameters encourages their clinical implementation.

SCN5A Mutations in Brugada Syndrome Are Associated with Increased Cardiac Dimensions and Reduced Contractility

Background The cardiac sodium channel (Nav1.5) controls cardiac excitability. Accordingly, SCN5A mutations that result in loss-of-function of Nav1.5 are associated with various inherited arrhythmia syndromes that revolve around reduced cardiac excitability, most notably Brugada syndrome (BrS). Experimental studies have indicated that Nav1.5 interacts with the cytoskeleton and may also be involved in maintaining structural integrity of the heart. We aimed to determine whether clinical evidence may be obtained that Nav1.5 is involved in maintaining cardiac structural integrity. Methods Using cardiac magnetic resonance (CMR) imaging, we compared right ventricular (RV) and left ventricular (LV) dimensions and ejection fractions between 40 BrS patients with SCN5A mutations (SCN5a-mut-positive) and 98 BrS patients without SCN5A mutations (SCN5a-mut-negative). We also studied 18 age/sex-matched healthy volunteers. Results SCN5a-mut-positive patients had significantly larger end-diastolic and end-systolic RV and LV volumes, and lower LV ejection fractions, than SCN5a-mut-negative patients or volunteers. Conclusions Loss-of-function SCN5A mutations are associated with dilatation and impairment in contractile function of both ventricles that can be detected by CMR analysis.

Cardiac magnetic resonance imaging for noninvasive assessment of cardiovascular disease during the follow-up of patients with Kawasaki disease.

Background— Kawasaki disease (KD) is the most common cause of acquired coronary artery disease in childhood. In KD, the American Heart Association recommends echocardiography for routine coronary artery surveillance and nuclear perfusion scans and conventional coronary angiography in select patients. Cardiac MRI (CMRI) may be a noninvasive and radiation-free alternative. We applied CMRI during the follow-up of patients with KD and assessed the performance of CMRI compared with echocardiography. Methods and Results— Patients with KD aged ≥8 years were consecutively included. Sixty-three patients (median age, 14.6 years; 74.6% male sex) underwent a comprehensive CMRI protocol including adenosine stress testing to evaluate coronary artery anatomy, ischemia, and myocardial infarction. All patients underwent CMRI without significant complications. On CMRI, 23 coronary artery aneurysms (CAAs) were identified in 15 patients. CMRI detected thrombus formation in 6 CAAs in 4 patients, wall motion disturbances and ischemia in 4 patients, and delayed hyperenhancement indicating myocardial infarction in 5 patients. Wall motion and perfusion abnormalities were noted in territories supplied by affected coronary arteries. CMRI results were compared with recent echocardiography findings. In 6 of the 15 patients with CAAs on CMRI, CAAs were not detected by echocardiography. Conclusions— A comprehensive CMRI protocol including adenosine stress testing is feasible to identify coronary artery pathology, ischemia, and myocardial infarction in former patients with KD and compares favorably with echocardiography. CMRI may be used as a noninvasive and radiation-free imaging method for coronary artery surveillance during the long-term follow-up of patients with KD.

Frequency of coronary ostial aneurysms after aortic root surgery in patients with the Marfan syndrome

Coronary ostial aneurysm is a common finding in patients with Marfans syndrome after aortic root surgery, especially in patients who are greater than or equal to35 years of age at time of surgery

Right ventricular end-diastolic volume combined with peak systolic blood pressure during exercise identifies patients at risk for complications in adults with a systemic right ventricle.

OBJECTIVESnThe aim of this study was to identify which patients with a systemic right ventricle are at risk for clinical events.nnnBACKGROUNDnIn patients with congenitally or atrially corrected transposition of the great arteries, worsening of the systemic right ventricle is accompanied by clinical events such as clinical heart failure or the occurrence of arrhythmia.nnnMETHODSnAt baseline, all subjects underwent electrocardiography, echocardiography, cardiopulmonary exercise testing, and cardiovascular magnetic resonance imaging. Clinical events comprised death, vascular events, tricuspid regurgitation requiring surgery, worsening heart failure, and (supra)ventricular arrhythmia. A Cox proportional hazards analysis was used to assess the most valuable determinants of clinical events.nnnRESULTSnA total of 88 patients with a mean age of 33 years were included in the study. Sixty-five percent were men, and 28% had congenitally corrected transposition of the great arteries. During a follow-up period of 4.3 years, 31 patients (35%) experienced 46 clinical events for an annual risk of 12%. Right ventricular end-diastolic volume index measured by means of cardiovascular magnetic resonance imaging or multirow detector computed tomography (hazard ratio: 1.20; pxa0< 0.01) and peak exercise systolic blood pressure (hazard ratio: 0.86; pxa0= 0.02) were the strongest determinants of clinical events. Patients with a right ventricular end-diastolic volume index above 150 ml/m(2) and peak exercise systolic blood pressure below 180 mm Hg were most likely to experience clinical events with an annual event rate of 19% versus 0.9% in patients without these risk factors.nnnCONCLUSIONSnPatients with a right ventricular end-diastolic volume index above 150 ml/m(2) and peak exercise systolic blood pressure below 180 mm Hg had a 20-fold higher annual event rate than patients without these risk factors. Regular cardiovascular magnetic resonance imaging and exercise testing are important in the risk assessment of these patients.

Intrinsic biventricular dysfunction in Marfan syndrome

Background Marfan syndrome (MFS) is an autosomal, dominantly inherited, connective tissue disorder usually caused by a mutation in the fibrillin-1 gene (FBN1). As fibrillin-1 is a component of the extracellular matrix of the myocardium, mutations in FBN1 may cause impairment of ventricular function. Furthermore, aortic elasticity is decreased in patients with MFS, which might also impair ventricular function. We assessed biventricular function and the influence of aortic elasticity in patients with MFS by means of cardiac MRI. Methods and results Cardiac magnetic resonance was performed in 144 patients with MFS without significant valvular dysfunction, previous cardiac surgery or previous aortic surgery. Biventricular diastolic and systolic volumes were measured, and ejection fractions were calculated. Flow wave velocity, a measurable derivative of aortic elasticity, was measured between the ascending aorta and the bifurcation. When compared to healthy controls (n=19), left ventricular ejection fraction (LVEF) was impaired in patients with MFS (53%±7% vs 57%±4%, p<0.005), as was right ventricular ejection fraction (RVEF) (51%±7% vs 56%±4%, p<0.005). LVEF and RVEF were strongly correlated. (r=0.7, p<0.001). No significant differences were found between patients with β-blocker treatment and those without. There was no correlation between aortic elasticity as measured by flow wave velocity and LVEF. Conclusions Biventricular ejection fraction was impaired in patients with MFS, and the impairment was independent of aortic elasticity and β-blocker usage. There was also a strong correlation between LVEF and RVEF. Our findings suggest intrinsic myocardial dysfunction in patients with MFS. Clinical trial registration http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1423. Unique Identifier: NTR1423

Comparison of aortic elasticity in patients with the marfan syndrome with and without aortic root replacement.

In conclusion, MRI enables the assessment of aortic elasticity in patients with Marfans syndrome with elective ARR. Aortic elasticity between Marfan patients with and without aortic root replacement showed no differences.