Mitral Stenosis: Making the diagnosis

The case of a 60-year-old man illustrates a number of important features of rheumatic heart disease (RHD). The patient’s age of presentation was late (>50 yo) and he had no history of predisposing condition for RHD but served in the South Pacific when he was in the US Navy. RHD was limited to mitral stenosis in this patient and his presentation of heart failure was late. His ECG revealed ample evidence of right ventricular enlargement, and echocardiography demonstrated severe mitral stenosis, enlarged right ventricle and right atrium and marked pulmonary hypertension. Because percutaneous balloon mitral valve commissurotomy was precluded by the degree of mitral valve calcification, he underwent successful surgical valve replacement with relief of symptoms. Although RHD is rarely encountered in North America and Europe, it remains a major cause of mortality in the developing nations.

Histological and molecular characterization of human aortic stenosis: a matter of sex

Introduction Aortic stenosis (AS) is the most common heart valve disease and it is strongly prevalent with elderly. AS is a progressive, degenerative disease associated with fibrosis and calcification of the valve leaflets. Surgical valve replacement is the only treatment available. Molecular, cellular and interstitial events activate multifactorial and complex cues with a significant contribution by valve interstitial cells (VICs). Despite male sex is a risk factor for developing AS, there is scant information on sex-specific differences in aortic valve (AV) biology or pathology. Purpose The aim of our study was to analyse sex-specific differences in aortic valves from AS patients. Methods 185 patients with severe AS undergoing surgical valve replacement were recruited. 149 AVs (66 women; 83 men) were used for ex vivo analyses. Human VICs were isolated from 36 AVs (12 women; 24 men) for in vitro experiments. AVs structure were evaluated by haematoxylin-eosin, Movat, Alizarin Red, Congo red and Alcian blue/Sirius Red staining and immunohistochemistry. Western blot, ELISA and zymography were used for molecular biology studies. Results AVs from men presented increased inflammatory infiltrates (CD68 and CD45 positive cells) as compared to women. Complementarily, AVs from men exhibited higher levels of the inflammatory molecules interleukin (IL)-6 and IL-1b and RANTES. In line with these results, oxidative stress markers (eNOS, myeloperoxidase, malondialdehyde and nitrotyrosine) were upregulated in male AVs. Concerning, fibrosis, increased levels of collagen type I, fibronectin and syndecan-1 were found in AVs from men. Extracellular matrix (ECM) remodelling was characterized by reduced metalloproteinase-1 expression and increased tissue inhibitor of metalloproteinase-2 expression in male AVs. Importantly, calcification and osteogenic markers (bone morphogenetic protein-9, periostin, osteocalcin and Sox-9) was greatly enhanced in men AVs as compared to women. These findings were confirmed in isolated VICs. At baseline, male VICs presented higher myofibroblast-like phenotype than female VICs. In line with our ex vivo results, male VICs exhibited increased inflammatory, oxidative stress, fibrotic and osteogenic differentiation markers. Conclusions Our results suggest that the mechanisms driving the AV pathogenesis could be different in men and women patients with the same AS severity. Male AVs and isolated VICs presented more inflammation, oxidative stress, fibrosis and ECM remodelling including extensive calcification as compared to female. A better knowledge of the pathophysiological pathways in AVs and VICs will allow developing sex-specific options for AS treatment. FUNDunding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III

Clinical Significance of Ventricular Tachyarrhythmias in Patients Undergoing Valve Replacement: A Nationwide Population-Based Study

Background: The clinical significance and outcomes of ventricular tachyarrhythmias (VTa) in patients undergoing valve replacement have rarely been reported.Objective: This study aimed to investigate the incidence and outcome of VTa after surgical valve replacement.Methods: We conducted a population-based retrospective cohort study using data obtained from the Taiwan National Health Insurance Research Database. In total, 10,212 patients were selected after 1:1 propensity-score matching based on the type of prosthetic valve used (mechanical vs. bioprosthetic). Various outcomes during long-term follow-up were analyzed.Results: After a median follow-up period of 59.6 months, the crude incidence rate of VTa after surgical valve replacement was 4.8/1,000 person-years, and the cumulative incidence of VTa persistently increased after surgery. Furthermore, the occurrences of VTa after valve replacement significantly increased the risk of cardiovascular (CV) death (P < 0.001, HR 1.67, 95% CI 1.41–1.96), stroke- (P < 0.001, HR 1.66, 95% CI 1.37–2.01), atrial fibrillation- (P < 0.001, HR 2.80, 95% CI 2.42–3.24), and congestive heart failure-related hospitalization (P < 0.001, HR 2.61, 95% CI 2.30–2.95). Among patients with VTa, all-cause mortality (P = 0.001, HR 0.49, 95% CI 0.32–0.75) and CV death (P = 0.047, HR 0.58, 95% CI 0.34–0.99) in those with implantable cardioverter-defibrillator (ICD) implantation were lower than those without.Conclusion: The crude incidence rate of VTa after surgical valve replacement was 4.8/1,000 person-years, and the cumulative incidence of VTa persistently increased during follow-up. The presence of VTa after surgical valve replacement increases hospitalization and CV death, while ICD implantation reduced the mortality rate in these patients.

TAVI Beyond 3 Years: Durability and Predictors for Survival

The use of transcatheter aortic valve implantation (TAVI) has greatly increased over the past 2 decades and now has overtaken surgical aortic valve replacement. We have limited data regarding the long-term durability of TAVI and the predictors of survival. Calcification, inflammation, fibrous tissue deposition, and mechanical stress are important in the structural deterioration of surgical bioprosthetic valves and likely contribute to TAVI durability. However, TAVI has several differences to surgical valve replacement such as valve preparation, valve to native anatomy interaction, and valve sizing which all likely contribute to durability and long-term survival. Most procedures have been performed on older patients and therefore long-term follow-up studies have noted mortality of approximately 50% at 5 years and 75% by 7 years. Current data are limited by the high mortality of patients who have received TAVI often as a result of age, frailty, and other competing comorbidities. TAVI as compared with surgical valve replacement is associated with several differences including higher conduction abnormalities (i.e., need for pacemakers) and paravalvular leak, both of which may affect long-term morbidity and mortality. In this review, we discuss the current status of our knowledge and identify areas that require further investigation.

Echocardiographic evaluation of paravalvular aortic regurgitation of a patient with recurrent aortic valve replacements

Paravalvular regurgitation (PVR) is a serious complication after surgical valve replacement. Echocardiography is the gold standard technique to assess the severity of PVR with an integrated approach.A 48-year-old male underwent aortic valve replacement due to infective endocarditis (IE). During in-hospital cardiac rehabilitation after a redo surgery for a new IE three years later, an echo-free anterior space around the valve with several PVRs through transthoracic echocardiography (TTE) was identified. On transesophageal echocardiography (TOE) a double PVR (anterior and posterior) with abscessual cavity was detected. The patient’s conditions worsened within six months with hemodynamic instability: a massive PVR due to a large abscess cavity next to the right cusp was confirmed by TTE and TOE and a third surgery was carried out. On the third admission at our Rehabilitation Unit the echo features were normal. Patient did not report any cardiovascular symptoms at 1 year follow-up.