Clinical characteristics of ruptured chordae tendineae in hospitalized patients: primary tear versus infective endocarditis

An Unusual Presentation of Acute Severe Mitral Regurgitation

Mitral regurgitation (MR) results from retrograde blood flow from the left ventricle to the left atrium. Common etiologies of acute severe MR include papillary muscle rupture from myocardial infarction, leaflet perforation in infective endocarditis, chordal rupture (pop) in myxomatous valve disease, acute rheumatic fever with carditis, or functional MR due to cardiomyopathies, myocarditis or Takotsubo cardiomyopathy. Here, we present an unusual case of acute severe MR due to ruptured chordae tendineae likely secondary to degenerative valve disease. A 59-year-old male with a past medical history of hypertension and renal calculi was evaluated in the outpatient office for a urologic procedure. He was sent to the emergency room with left-sided chest pain, 6/10 in intensity, burning in nature, and non-radiating with no aggravating and relieving factors. He had nausea and vomiting for the past three days. He reported similar chest pain at rest and on exertion multiple times over the past year. He also had a chronic cough with no recent changes. His examination was unremarkable. Chest X-ray showed interstitial lung markings. Electrocardiography revealed an old right bundle branch block, but no ST/T-wave changes. He was admitted and treated for atypical pneumonia with ceftriaxone and azithromycin. The following morning, he complained of persistent chest pain 9/10 in intensity which improved with nitroglycerin. His examination revealed a new onset holosystolic murmur heard over the precordium. A two-dimensional echocardiogram showed a preserved ejection fraction of 55-60%, severe MR with eccentric jet, concerning for partially flail leaflet of the mitral valve. He was transferred to the university hospital for mitral valve replacement. Patients with acute rupture of chordae tendineae usually progress to severe mitral valve regurgitation. These patients usually present with pulmonary edema, signs of heart failure, and cardiogenic shock. Papillary muscle dysfunction, as well as partial or complete rupture of the mitral chordae can be detected as a new-onset holosystolic murmur and can be a crucial sign for early recognition. In our case, the patient developed a new holosystolic murmur on day two of admission which was recognized early, and prompt surgical intervention was performed.

Exploring Unusual Cardiac Complications: Chorda Tendinea Rupture and Pulmonary Valve Vegetation in Infective Endocarditis-A Comprehensive Review

Infective endocarditis (IE) is a severe infection of the endocardium, frequently involving heart valves, and is associated with significant morbidity and mortality. At the same time, traditional complications of IE, such as valvular dysfunction and embolic events, are well-documented, and uncommon cardiac manifestations, such as chorda tendinea rupture and pulmonary valve vegetation, present unique diagnostic and management challenges. This comprehensive review explores the pathophysiology, clinical presentation, diagnostic strategies, and management approaches for IE's chorda tendinea rupture and pulmonary valve vegetation. Through a detailed examination of the literature and discussion of clinical scenarios, we highlight the importance of recognizing these rare complications and discuss the implications for clinical practice. Additionally, we identify knowledge gaps and propose areas for future research to enhance further our understanding and management of these unusual cardiac complications in IE. This review aims to provide clinicians with valuable insights to improve patient care and outcomes in the challenging setting of infective endocarditis.

Fluid-Structure Interaction Analysis of Subject-Specific Mitral Valve Regurgitation Treatment with an Intra-Valvular Spacer

Mitral regurgitation imposes a significant symptomatic burden on patients who are not candidates for conventional surgery. For these patients, transcatheter repair and replacement devices are emerging as alternative options. One such device is an intravalvular balloon or spacer that is inserted between the mitral valve leaflets to fill the gap that gives rise to mitral regurgitation. In this study, we apply a large-deformation fluid-structure interaction analysis to a fully 3D subject-specific mitral valve model to assess the efficacy of the intra-valvular spacer for reducing mitral regurgitation severity. The model includes a topologically 3D subvalvular apparatus with unprecedented detail. Results show that device fixation and anchoring at the location of the subject’s regurgitant orifice is imperative for optimal reduction of mitral regurgitation.

Fluid-Structure Interaction Analysis of Ruptured Mitral Chordae Tendineae

The chordal structure is a part of mitral valve geometry that has been commonly neglected or simplified in computational modeling due to its complexity. However, these simplifications cannot be used when investigating the roles of individual chordae tendineae in mitral valve closure. For the first time, advancements in imaging, computational techniques, and hardware technology make it possible to create models of the mitral valve without simplifications to its complex geometry, and to quickly run validated computer simulations that more realistically capture its function. Such simulations can then be used for a detailed analysis of chordae-related diseases. In this work, a comprehensive model of a subject-specific mitral valve with detailed chordal structure is used to analyze the distinct role played by individual chordae in closure of the mitral valve leaflets. Mitral closure was simulated for 51 possible chordal rupture points. Resultant regurgitant orifice area and strain change in the chordae at the papillary muscle tips were then calculated to examine the role of each ruptured chorda in the mitral valve closure. For certain subclassifications of chordae, regurgitant orifice area was found to trend positively with ruptured chordal diameter, and strain changes correlated negatively with regurgitant orifice area. Further advancements in clinical imaging modalities, coupled with the next generation of computational techniques will enable more physiologically realistic simulations.

Activated human valvular interstitial cells sustain interleukin-17 production to recruit neutrophils in infective endocarditis

The mechanisms that underlie valvular inflammation in streptococcus-induced infective endocarditis (IE) remain unclear. We previously demonstrated that streptococcal glucosyltransferases (GTFs) can activate human heart valvular interstitial cells (VIC) to secrete interleukin-6 (IL-6), a cytokine involved in T helper 17 (Th17) cell differentiation. Here, we tested the hypothesis that activated VIC can enhance neutrophil infiltration through sustained IL-17 production, leading to valvular damage. To monitor cytokine and chemokine production, leukocyte recruitment, and the induction or expansion of CD4(+) CD45RA(-) CD25(-) CCR6(+) Th17 cells, primary human VIC were cultured in vitro and activated by GTFs. Serum cytokine levels were measured using an enzyme-linked immunosorbent assay (ELISA), and neutrophils and Th17 cells were detected by immunohistochemistry in infected valves from patients with IE. The expression of IL-21, IL-23, IL-17, and retinoic acid receptor-related orphan receptor C (Rorc) was upregulated in GTF-activated VIC, which may enhance the proliferation of memory Th17 cells in an IL-6-dependent manner. Many chemokines, including chemokine (C-X-C motif) ligand 1 (CXCL1), were upregulated in GTF-activated VIC, which might recruit neutrophils and CD4(+) T cells. Moreover, CXCL1 production in VIC was induced in a dose-dependent manner by IL-17 to enhance neutrophil chemotaxis. CXCL1-expressing VIC and infiltrating neutrophils could be detected in infected valves, and serum concentrations of IL-17, IL-21, and IL-23 were increased in patients with IE compared to healthy donors. Furthermore, elevated serum IL-21 levels have been significantly associated with severe valvular damage, including rupture of chordae tendineae, in IE patients. Our findings suggest that VIC are activated by bacterial modulins to recruit neutrophils and that such activities might be further enhanced by the production of Th17-associated cytokines. Together, these factors can amplify the release of neutrophilic contents in situ, which might lead to severe valvular damage.

Acute rupture of chordae tendineae of the mitral valve in infants: a nationwide survey in Japan exploring a new syndrome

BACKGROUND

Recently, infant cases of acute heart failure attributable to rupture of the mitral chordae tendineae have been reported. However, little is known about the pathogenesis and clinical course of this condition.

METHODS AND RESULTS

Ninety-five children with rupture of mitral chordae tendineae were identified in nationwide surveys of Japan diagnosed from 1995 to 2013. The clinical manifestations, management strategies, and prognosis were investigated. Eighty-one (85%) patients were between 4 and 6 months (median, 5 months) of age. In 63 (66%) patients, rupture occurred during the spring or summer. The underlying conditions before rupture included Kawasaki disease (10 cases), maternally derived anti-SSA antibodies (2 cases), and infective endocarditis (1 case). Surgery was performed in 80 patients (94 operations), and the final operations included plasty of mitral chordae in 52 cases and mechanical valve replacement in 26 cases. The histopathologic examinations of the mitral valves and chordae (n=28) revealed inflammatory reactions with predominant mononuclear cell infiltration in 18 cases (64%) and increased fibrous and myxoid tissue in 11 cases (39%), suggesting that nonbacterial infectious or autoimmune endocarditis and myxoid changes are involved in the pathogenesis. Eight patients (8.4%) died before (n=6) and shortly after (n=2) the operation, and significant neurological complications persisted in 10 cases (11%).

CONCLUSIONS

Acute heart failure attributable to rupture of the mitral chordae tendineae in infants is a unique disease resulting from diverse causes. This condition should be recognized as a significant cardiovascular disorder that may cause sudden onset of cardiogenic shock and death in infants.

Matrix metalloproteinase-1 mitral expression and -1607 1G/2G gene promoter polymorphism in mitral chordae tendinae rupture

Understanding the pathogenesis of mitral chordae tendinae rupture (MCTR) is essential for identification of risk factors. Mitral matrix metalloproteinase (MMP) triggers the signal cascade that instigates cardiac fibrosis, which may be a predisposing factor in MCTR. We investigated associations among MMP1 expression, MMP1 -1607 1G/2G polymorphism and mitral chordae tendinae rupture (MCTR). This study enrolled 185 patients (group A) receiving mitral valve replacement. Group A included 65 patients with MCTR and 120 controls without MCTR. MMP1 was assessed on a semiquantitative scale (0-3) by immunohistochemical staining. For genetic association study, another 227 subjects were recruited for group B, including 75 with MCTR and 152 controls. The gene polymorphisms were analyzed by polymerase chain reaction. In group A, MCTR patients had a higher MMP1 expression compared to controls (P < 0.001). Binary regression analysis showed the variation in the MCTR patients was independently explained by MMP1 (P = 0.027). Hypertension and MMP1 staining had a synergistic effect on the MCTR occurrence (P < 0.001). In group B, MMP1 -1607 1G allele was increased in patients with MCTR compared to controls (P = 0.014). The odds ratio for the 1G/1G genotype to the 2G/2G genotype was 3.22 (P = 0.009). Univariate and logistic regression analysis showed an independent association between MCTR and MMP1 -1607 1G/2G polymorphism (P = 0.028 and 0.032, respectively). Since MMP1 mitral expression and -1607 1G/2G polymorphism were associated with MCTR independently of other baseline characteristics, MMP1 may play a role in the individual susceptibility to MCTR.

Synergistic effect of mitral expression of tissue inhibitor of metalloproteinase-2 with hypertension on the occurrence of mitral chordae tendinae rupture

OBJECTIVES

We previously found the association between mitral chordae tendinae ruptures (MCTR) and hypertension. Tissue inhibitor of metalloproteinase-2 (TIMP2), which expresses differently under pressure loads, could trigger a signal cascade instigating cardiac fibrosis, possibly predisposing to MCTR. We aimed to elucidate the relationship between the TIMP2 and hypertension and the effect they may have on the occurrence of MCTR.

METHODS

Using a cross-sectional study in a tertiary medical center in Taiwan, we enrolled 186 patients who had received mitral valve replacements and classified them into two groups: 64 (34%) with MCTR and 122 (66%) without MCTR. Expression of mitral TIMP2 was assessed on a semiquantitative scale (grade 0-3) by immunohistochemical staining using antibodies against TIMP2.

RESULTS

TIMP2 expression was significantly higher in MCTR patients (P < 0.001). Multiple logistic regression analysis showed four independent risk factors: TIMP2 [odds ratio (OR) = 1.82, 95% confidence interval (CI) = 1.18-2.81, P = 0.007], hypertension (OR = 2.40, CI = 1.08-5.34, P = 0.032), rheumatic heart disease (OR = 0.18, CI = 0.05-0.70, P = 0.014), and left ventricular end-diastolic dimension (OR = 1.10, CI = 1.05-1.15, P < 0.001). Among nonhypertensive patients, the higher expression of TIMP2 (grade 2 and 3 vs. 0 and 1) was associated with a 3.27-fold risk. However, hypertensive patients with higher TIMP2 expression had a significantly 10-fold higher risk (P < 0.001 for interaction).

CONCLUSION

Mitral TIMP2 expression is higher in patients with MCTR and there is a synergistic effect of mitral TIMP2 staining with hypertension on the occurrence of MCTR.

Efficacy of intravenous immunoglobulin in chronic idiopathic pericarditis: report of four cases

Human intravenous immunoglobulins (hIVIgs) are used in two broad categories of diseases: immunodeficiency and autoimmunity. Among the immune-mediated diseases hIVIgs are of benefit in idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, and dermatomyositis. Chronic idiopathic pericarditis (CIP) is a chronic disease of unknown origin characterized by recurrent episodes of pericardial inflammation. The cause of the recurrence is unknown, although in some cases it may be traced to a viral infection and to the presence of antimyocardial antibodies. Since a viral infection can induce an autoimmune process through a mechanism of molecular mimicry, and since the optimal therapy for prevention of the recurrences has not been established, we reasoned that treatment with hIVIgs could be beneficial in our patients unresponsive to previous immunosuppressive therapies. We describe four patients affected by CIP treated with monthly high-dose hIVIgs (0.4 g/kg daily for 5 consecutive days) for five times followed by administration every 2 months. Three of the four patients could permanently discontinue steroid therapy and are still in remission after years of follow-up. Our experience suggests that hIVIgs therapy may be a useful and safe treatment for CIP in steroid-dependent patients.