Contemporary evaluation and treatment of tricuspid regurgitation.

Valvular heart disease is a global health burden with substantial mortality. The left-sided valvular diseases have been extensively described using the robust treatment strategies available. By contrast, the right-sided diseases, particularly the tricuspid valve (TV) and associated regurgitation, still have much to be delineated. Worsening tricuspid regurgitation (TR) is associated with increased mortality; the non-invasive management is suboptimal; and surgical approaches carry significant risk. With advances in multimodality imaging, 3D echocardiography, improved understanding of TV anatomy, and pathophysiological mechanisms of primary and secondary regurgitation, as well as favorable data with transcatheter therapies, the field of TV management is rapidly evolving. This review aims to highlight pathophysiological mechanisms of TR, describe echocardiographic approaches to diagnosis and TV interrogation, and outline the latest transcatheter developments.

Indispensable Role of Multimodality Imaging in Diagnosis and Management of Coronary Arteriovenous Fistulas.

We describe a patient with right coronary artery to coronary sinus fistula requiring surgical elimination. The decision process in managing fistulas depends on the size, site of origin, and symptoms caused by the fistula. We highlight the pivotal role of multimodality cardiovascular imaging in the diagnosis and management of coronary fistulas. (Level of Difficulty: Intermediate.).

Acute Perimyocarditis Unmasking Anomalous Coronary Artery: Is Treating the Inflammation Enough? Does Surgery Fix All?

We report the case of a patient with anomalous right coronary artery (RCA) unmasked by acute perimyocarditis who continued to have ischemic symptoms despite total resolution of perimyocarditis and required surgical intervention of the anomalous RCA. This case was further complicated by ventricular arrhythmia after surgical repair. Collaboration among different cardiac specialists was essential in this case. (Level of Difficulty: Advanced.).

Off-pump surgery for giant right coronary artery aneurysms.

Coronary artery aneurysms larger than 5 cm are exceedingly rare, and a standard treatment for them is lacking. We report two cases of giant right coronary artery aneurysms successfully treated by off-pump resection of the aneurysm and bypass grafting. The controversy surrounding the proper management of such cases is discussed.

Surgical repair of tetralogy of Fallot using autologous right atrial appendages: short- to mid-term results.

OBJECTIVES: The prevention of pulmonary insufficiency (PI) is a crucial part of the tetralogy of Fallot repair. Many techniques have been introduced to construct valves from different materials for the right ventricular outflow tract, including the most commonly constructed monocusp valves. We are introducing a new bicuspid valve made intraoperatively using the autologous right atrial appendage (RAA) to prevent PI in these patients. METHODS: The RAA valve was constructed and used in 21 patients with tetralogy of Fallot. The effective preservation of the native valve was impossible in all patients because of either a severe valve deformity or a small annulus. The RAA valve was created after ventricular septal defect closure and right ventricular outflow tract myectomy and was covered with a bovine transannular pericardial patch. The perioperative data were evaluated, and the echocardiography results were assessed immediately after operations and in follow-up with a median of 10.5 months. The data were retrospectively compared with 10 other patients with similar demographic data but with only transannular patches. RESULTS: The mean age of the patients was 13.3 months. No mortality or related morbidity occurred after repair using the RAA valve. The PI severity early after the operation was trivial or no PI in 18 patients, and mild PI was observed in 3 patients, which progressed to moderate PI in one of them in the mean 12-month follow-up period. Fifteen patients had mild or no pulmonary stenosis, while moderate pulmonary stenosis was observed in 6 others. Compared with the other 10 patients with only transannular patches, the RAA valve patients had prolonged operative and clamping times, but no difference in postoperative course and shorter hospital stays. The degree of PI was, of course, significantly less in the RAA valve patients, but pulmonary stenosis was the same. CONCLUSIONS: The RAA valve construction is a safe and effective technique to prevent PI after the tetralogy of Fallot repair, at least in terms of short- and mid-term results. A longer follow-up period is needed to confirm if this new valve can eliminate or significantly delay the need for pulmonary valve replacement in these patients.

Perioperative management of patients on adenosine diphosphate inhibitors in the era of drug-eluting stents: review of the literature and clinical implications.

The current adenosine diphosphate inhibitors, ticlopidine and clopidogrel, are thienopyridine compounds that inhibit adenosine diphosphate mediated platelet aggregation. They interfere with platelet activation by selectively and irreversibly blocking P2Y12 sub-unit of the adenosine diphosphate receptor on the surface of platelets. This provides an antiplatelet effect that is additive to the inhibition of the thromboxane A2 pathway by aspirin. Dual antiplatelet therapy is extensively used in cardiovascular medicine. Randomized controlled trials have substantiated the fact that thrombotic complications after percutaneous coronary intervention procedures can be decreased by using dual antiplatelet therapy. However, there is a concern of bleeding due to enhanced and irreversible platelet inhibition in patients who will require any operation including coronary artery bypass grafting while on adenosine diphosphate inhibitors. This applies to a large population of patients requiring either coronary artery bypass grafting after angiographic definition of their coronary anatomy, or patients requiring semi-elective or urgent operation while under dual antiplatelet therapy. This concern is more present in era of drug-eluting stents, where long-term use of dual antiplatelet therapy is encouraged, and the incidence of late thrombosis after late cessation of adenosine diphosphate inhibitors is increasingly surfacing in the literature. The goal this review is to provide the medical chemistry of most commonly used adenosine diphosphate inhibitors, examine the literature on the effect of adenosine diphosphate inhibitors in hemorrhagic-related complications after surgical intervention, and provide the ramifications and alternatives in modern clinical practice.

Left ventricular-right atrial communication (Gerbode-type defect) following mitral valve replacement.

We report a case of left ventricular-right atrial communication in a 51-year-old patient following mitral valve replacement. Transesophageal echocardiography was used to make the diagnosis, and the communication was closed surgically using pledgeted sutures. The surgical management of such defects is discussed.

Cardiac Transplantation in the New Era.

The prevalence of heart failure continues to rise due to the aging population and longer survival of people with conditions that lead to heart failure, eg, hypertension, diabetes, and coronary artery disease. Although medical therapy has had an important impact on survival of patients and improving quality of life, heart transplantation remains the definitive therapy for patients that eventually deteriorate. Since the first successful heart transplantation in 1967, significant improvements have been made regarding donor and recipient selection, surgical techniques, and postoperative care. However, the number of potential organ donors has not changed and the growing number of patients in need for transplantation has resulted an increase in waiting list time, and the need for mechanical support. To overcome this issue, the United Network for Organ Sharing implemented an allocation system to prioritize the sickest patients on the list to receive organs. Despite the careful selection of patients, pretransplant immunological screening, and multidrug immunosuppressive regimens, acute and chronic rejections occur and potentially limit graft and patient survival. Treatment for rejection largely depends on the type of rejection, the presence of hemodynamic compromise, and time after transplantation. The limiting factor for long-term graft survival is allograft vasculopathy, an immune-mediated process causing diffuse narrowing of the coronary arteries. Percutaneous coronary intervention and coronary artery bypass surgery are often not an option for this vasculopathy due to the lack of focal lesions, and retransplantation is the only option in appropriate patients.

Succinate dehydrogenase gene mutations in cardiac paragangliomas.

Pheochromocytomas and paragangliomas are chromaffin cell tumors arising from neuroendocrine cells. At least 1/3 of paragangliomas are related to germline mutations in 1 of 17 genes. Although these tumors can occur throughout the body, cardiac paragangliomas are very rare, accounting for <0.3% of mediastinal tumors. The purpose of this study was to determine the clinical characteristics of patients with cardiac paragangliomas, particularly focusing on their genetic backgrounds. A retrospective chart analysis of 15 patients with cardiac paragangliomas was performed to determine clinical presentation, genetic background, diagnostic workup, and outcomes. The average age at diagnosis was 41.9 years. Typical symptoms of paraganglioma (e.g., hypertension, sweating, palpitations, headache) were reported at initial presentation in 13 patients (86.7%); the remaining 2, as well as 4 symptomatic patients, initially presented with cardiac-specific symptoms (e.g., chest pain, dyspnea). Genetic testing was done in 13 patients (86.7%); 10 (76.9%) were positive for mutations in succinate dehydrogenase (SDHx) subunits B, C, or D. Thirteen patients (86.7%) underwent surgery to remove the paraganglioma with no intraoperative morbidity or mortality; 1 additional patient underwent surgical resection but experienced intraoperative complications after removal of the tumor due to co-morbidities and did not survive. SDHx mutations are known to be associated with mediastinal locations and malignant behavior of paragangliomas. In this report, the investigators extend the locations of predominantly SDHx-related paragangliomas to cardiac tumors. In conclusion, cardiac paragangliomas are frequently associated with underlying SDHx germline mutations, suggesting a need for genetic testing of all patients with this rare tumor.

Inhibiting CXCL12 blocks fibrocyte migration and differentiation and attenuates bronchiolitis obliterans in a murine heterotopic tracheal transplant model.

OBJECTIVES: Fibrocytes are integral in the development of fibroproliferative disease after lung transplantation. Undifferentiated fibrocytes (CD45+anti-collagen 1+CXCR4+) preferentially traffic by way of the CXCR4/CXCL12 axis and differentiate into smooth muscle actin-producing (CD45+CXCR4+α-smooth muscle actin+) cells. We postulated that an antibody directed against CXCL12 would attenuate fibrocyte migration and fibro-obliteration of heterotopic tracheal transplant allografts. METHODS: A total alloantigenic mismatch murine heterotopic tracheal transplant model of obliterative bronchiolitis was used. The mice were treated with either goat-anti-human CXCL12 F(ab')(2) or goat IgG F(ab')(2). Buffy coat, bone marrow, and trachea allografts were collected and analyzed using flow cytometry. Tracheal luminal obliteration was assessed using hematoxylin-eosin and Direct Red 80 collagen stain. RESULTS: Compared with the controls, the anti-CXCL12-treated mice showed a significant decrease in tracheal allograft fibrocyte populations at 7 and 21 days after transplantation. Bone marrow and buffy coat aspirates showed the same trend at 7 days. In the anti-CXCL12-treated mice, there was a 35% decrease in luminal obliteration at 21 days (65% vs 100% obliterated; interquartile range, 38% vs 10%; P = .010) and decreased luminal collagen deposition at 21 and 28 days after transplantation (P = .042 and P = .012, respectively). CONCLUSIONS: Understanding the role of fibrocytes in airway fibrosis after lung transplantation could lead to a paradigm shift in treatment strategy. Anti-CXCL12 antibody afforded protection against infiltrating fibrocytes and reduced the deterioration of the tracheal allografts. Thus, the CXCR4/CXCL12 axis is a novel target for the treatment of fibro-obliteration after lung transplantation, and the quantification of fibrocyte populations could provide clinicians with a biomarker of fibrosis, allowing individualized drug therapy.

The universal bed model for patient care improves outcome and lowers cost in cardiac surgery.

OBJECTIVE: With the escalating demands to increase the efficiency and decrease the cost, innovations in postoperative cardiac surgical patient care are needed. The universal bed model is an innovative care delivery system that allows patient care to be managed in one setting from postoperation to discharge. We hypothesized that the universal bed model in the context of cardiac surgery would improve outcomes and efficacy. METHODS: A total of 610 consecutive patients were admitted to the universal bed unit and prospectively entered into the Society of Thoracic Surgeons National Cardiac Database. Intensive care unit level of care was determined by acuity and staffing needs. Telemetry was employed from admission to discharge, and multidisciplinary rounds were conducted twice daily. Postoperative outcomes were recorded during hospital stay, and comparisons were made with the Society of Thoracic Surgeons National Cardiac Database using identical variables over the same period of time. RESULTS: Decreased ventilation time, intensive care unit and hospital stay, and reduction in the incidence of atrial fibrillation and infectious complications yielded a financial benefit in the universal bed group compared with the traditional model of admission. Stroke rate and in-hospital mortality were the same compared with regional and national centers. Compared with regional centers, there was an average cost savings between $6200 and $9500 per patient depending on the operation. Patient care satisfaction by independent survey was in the 99th percentile. CONCLUSIONS: The universal bed patient care model allows for expedient and efficacious care as measured by decreased length of intensive care unit and hospital stay, improved postoperative outcomes, patient satisfaction, and cost savings.

Concomitant left ventricular assist device placement and cryoablation for treatment of ventricular tachyarrhythmias associated with heart failure.

Refractory ventricular tachyarrythmias (VTs) are potentially life-threatening rhythms in patients with cardiomyopathies, particularly when they result in hemodynamic instability. Here we report two cases of patients with intractable ventricular tachyarrythmias that were unresponsive to anti-arrhythmic medications and repeated catheter ablation, and for whom concomitant cryoablation and left ventricular assist device implantation was successfully performed. Both patients tolerated the procedure well with no complications and were free from ventricular tachyarrythmias postoperatively. Concomitant surgical ventricular ablation at the time of left ventricular assist device surgery may be a reasonable approach for this subset of patients as it provides excellent visualization and the ability to ablate both epicardial and endocardial sites.

Brucellosis relapse causing prosthetic valve endocarditis and aortic root infective pseudoaneurysm.

We report a previously treated case of brucellosis and aortic root replacement, which became complicated by prosthetic valve endocarditis and a massive aortic root pseudoaneurysm. Preoperative blood and intraoperative pseudoaneurysm wall cultures were positive for Brucella, and the patient was managed successfully with a combination of surgical and medical treatment. Brucella endocarditis is further discussed.

Bronchiolitis obliterans syndrome occurs earlier in the post-lung allocation score era.

OBJECTIVES: In 2005, the time-based waiting list for lung transplantation was replaced by an illness/benefit lung allocation score (LAS). Although short-term outcomes after transplantation have been reported to be similar before and after the new system, little is known about long-term results. The objective of this study was to evaluate the impact of LAS on the development of bronchiolitis obliterans syndrome as well as on overall 3-year and bronchiolitis obliterans syndrome-related survival. METHODS: Data obtained from the United Network for Organ Sharing were used to review 8091 patients who underwent lung transplantation from 2002 to 2008. Patients were stratified according to time of transplantation into those treated before initiation of the LAS (pre-LAS group, January 2002-April 2005, n = 3729) and those treated after implementation of the score (post-LAS group, May 2005-May 2008, n = 4362). Overall, 3-year survivals for patient groups were compared using a univariate analysis, Cox proportional hazards model to generate a relative risk, and Kaplan-Meier curve analyses. RESULTS: During the 3-year follow-up period, bronchiolitis obliterans syndrome developed in 22% of lung transplant recipients (n = 1801). Although the incidence of postoperative bronchiolitis obliterans syndrome development was similar between groups, post-LAS patients incurred fewer bronchiolitis obliterans syndrome-free days (609 ± 7.5 vs 682 ± 9; P <.0001; log-rank test P = .0108) than did pre-LAS patients. Overall 3-year survival was lower in post-LAS patients and approached statistical significance (P = .05). Similarly, bronchiolitis obliterans syndrome-related survival was worse for patients in the post-LAS group (log-rank test P = .01). CONCLUSIONS: In the current LAS era, lung transplant recipients have significantly fewer bronchiolitis obliterans syndrome-free days after 3-year follow-up. Compared with the pre-LAS population, overall and bronchiolitis obliterans syndrome-related survival appears worse in the post-LAS era. Limitation of known risk factors for development of bronchiolitis obliterans syndrome-may prove even more important in this patient population.