Surgical and Transcatheter Mitral Valve Therapy: Medicare Utilization and Reimbursement.

BACKGROUND: We aimed to examine trends in the utilization and reimbursement of surgical and transcatheter mitral valve therapies and their changing relationship. METHODS: A query of administrative data on US Medicare beneficiaries undergoing mitral valve therapy was conducted from 2015 to 2020 using the Centers for Medicare and Medicaid Services Part B National Summary Data File. Inflation adjustment was to the 2020 Consumer Price Index. Trend analysis was quantified with growth rate and simple linear regression calculations. RESULTS: The annual number of all mitral valve procedures remained constant. Transcatheter mitral valve therapies increased by 313% with an increase of 1552 cases per year (P < .001), whereas surgical mitral valve therapies decreased by 31.4% with a decline of 1446 procedures per year (P = .004). As a proportion of all mitral valve therapies, surgical therapies decreased from 91.8% to 65.0%. Annual Medicare reimbursements for transcatheter and surgical mitral valve therapies mirrored the annual procedural trends. For transcatheter mitral valve therapies, per-case reimbursement decreased by 14.1% ($1283.18 to $1102.88), and for surgical mitral valve therapies, per-case reimbursement decreased by 3.8% ($1480.65 to $1424.57). CONCLUSIONS: Medicare utilization of mitral valve therapies has been stable in recent years, with growth of transcatheter volumes offset by a decrease in surgical volumes. This suggests that transcatheter therapy availability has not expanded the pool of patients with access to therapy. Nonetheless, case reimbursements decreased for both modalities.

Innovative Approach to Manage Transcatheter Aortic Valve Embolization.

We describe the case of a patient with an ascending aortic aneurysm who underwent valve-in-valve transcatheter aortic valve implantation, which was complicated by valve embolization. After a multidisciplinary discussion and an innovative approach, the free-floating embolized valve was anchored securely in the aortic arch with an uncovered aortic endovascular stent. (Level of Difficulty: Intermediate.).

Contemporary diagnosis and management of severe tricuspid regurgitation.

Many novel percutaneous interventions are being developed for application in the tricuspid valve position. At the present time in the United States, there are no commercially available transcathter devices for this application. This article reviews the growing evidence for diagnosing, imaging, and treating severe tricuspid regurgitation as well as the surgical and transcatheter options that are under current development and in various stages of clinical trials.

Smart Drain for Post-Cardiac Surgery Left Ventricular Volumes Evaluated in Large Animal Models.

BACKGROUND: Open heart surgeries for coronary arterial bypass graft and valve replacements are performed on 400,000 Americans each year. Unexplained hypotension during recovery causes morbidity and mortality through cerebral, kidney, and coronary hypoperfusion. An early detection method that distinguishes between hypovolemia and decreased myocardial function before onset of hypotension is desirable. We hypothesized that admittance measured from a modified pericardial drain can detect changes in left ventricular end-systolic, end-diastolic, and stroke volumes. METHODS: Admittance was measured from 2 modified pericardial drains placed in 7 adult female dogs using an open chest preparation, each with 8 electrodes. The resistive and capacitive components of the measured admittance signal were used to distinguish blood and muscle components. Admittance measurements were taken from 12 electrode configurations in each experiment. Left ventricular preload was reduced by inferior vena cava occlusion. Physiologic response to vena cava occlusion was measured by aortic pressure, aortic flow, left ventricle diameter, left ventricular wall thickness, and electrocardiogram. RESULTS: Admittance successfully detected a drop in left ventricular end-diastolic volume (P < .001), end-systolic volume (P < .001), and stroke volume (P < .001). Measured left ventricular muscle resistance correlated with crystal-derived left ventricular wall thickness (R2 = 0.96), validating the method's ability to distinguish blood from muscle components. CONCLUSIONS: Admittance measured from chest tubes can detect changes in left ventricular end-systolic, end-diastolic, and stroke volumes and may therefore have diagnostic value for unexplained hypotension.

Using a quality improvement initiative to reduce acute kidney injury during on-pump coronary artery bypass grafting.

INTRODUCTION: In response to a perceived high incidence of acute kidney injury following cardiopulmonary bypass at our institution, a quality improvement initiative consisting of a systematic change to a delivered oxygen (DO2) goal-directed perfusion practice was implemented. We sought to maintain DO2 > 270 mL/min/m2 to reduce the incidence of acute kidney injury. METHODS: 'The study population included all patients receiving isolated, non-emergent, on-pump coronary artery bypass grafting from January 2015 through December 2018, excluding patients requiring preoperative hemodialysis. DO2 goal-directed perfusion was instituted in February 2017. Acute kidney injury was defined using Acute Kidney Injury Network criteria. RESULTS: The pre-goal-directed perfusion cohort included 257 patients, and the post-goal-directed perfusion cohort included 226 patients. The DO2 was significantly higher in the post-goal-directed perfusion group (p < 0.001). Postoperative change in serum creatinine and incidence of acute kidney injury were significantly lower in the post-goal-directed perfusion group (p < 0.001, p = 0.001, respectively). Estimation with probit and ordered probit models support these findings. CONCLUSION: This initiative confirms previous assertions that DO2 is a critical intraoperative parameter and should direct perfusion intervention accordingly.

BARI 2D: A Reanalysis Focusing on Cardiovascular Events.

OBJECTIVE: To reanalyze the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial using a new composite cardiovascular disease (CVD) outcome to determine how best to treat patients with type 2 diabetes mellitus and stable coronary artery disease. PATIENTS AND METHODS: From January 1, 2001, to November 30, 2008, 2368 patients with type 2 diabetes mellitus and angiographically proven coronary artery disease were randomly assigned to insulin-sensitizing (IS) or insulin-providing (IP) therapy and simultaneously to coronary revascularization (REV) or no or delayed REV (intensive medical therapy [MED]), with all patients receiving intensive medical treatment. The outcome of this analysis was a composite of 8 CVD events. RESULTS: Four-year Kaplan-Meier rates for the composite CVD outcome were 35.8% (95% CI, 33.1%-38.5%) with IS therapy and 41.6% (95% CI, 38.7%-44.5%) with IP therapy (P=.004). Much of this difference was associated with lower in-trial levels of fibrinogen, C-reactive protein, and hemoglobin A1c with IS therapy. Four-year composite CVD rates were 32.7% (95% CI, 30.0%-35.4%) with REV and 44.7% (95% CI, 41.8%-47.6%) with MED (P<.001). A beneficial effect of IS vs IP therapy was present with REV (27.7%; 95% CI, 24.0%-31.4% vs 37.5%; 95% CI, 33.6%-41.4%; P<.001), but not with MED (43.6%; 95% CI, 39.5%-47.7% vs 45.7%; 95% CI, 41.6%-49.8%; P=.37) (homogeneity, P=.05). This interaction between IS therapy and REV was limited to participants preselected for coronary artery bypass grafting (CABG). The lowest composite CVD rates occurred in patients preselected for CABG and assigned to IS therapy and REV (17.3%; 95% CI, 11.8%-22.8%). CONCLUSION: In the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial, the IS treatment strategy and the REV treatment strategy each reduces cardiovascular events. The combination of IS drugs and CABG results in the lowest risk of subsequent CVD events. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00006305.

Trabecular cutting: a novel surgical therapy to increase diastolic compliance.

Heart failure with preserved ejection fraction (HFpEF) is a common cause of hospital admission in patients over 65 yr old and has high mortality. HFpEF is characterized by left ventricular (LV) hypertrophy that reduces compliance. Current HFpEF therapies control symptoms, but no existing medications or therapies can sustainably increase LV compliance. LV trabeculae develop hypertrophy and fibrosis that contribute to reduced LV compliance. This study expands our previous results in ex vivo human hearts to show that severing LV trabeculae increases diastolic compliance in an ex vivo working rabbit heart model. Trabecular cutting was performed in ex vivo rabbit hearts set up in a working heart perfusion system perfused with oxygenated Krebs-Henseleit buffer. A hook was inserted in the LV to cut trabeculae. End-systolic and end-diastolic pressure-volume relationships during transient preload reduction were recorded using an admittance catheter in the following three groups: control (no cutting; n = 9), mild cutting (15 cuts; n = 5), and aggressive cutting (30 cuts; n = 5). In a second experiment, each heart served as its own control. Hemodynamic data were recorded before and after trabecular cutting (n = 10) or sham cutting (n = 5) within the same heart. In the first experiments, trabecular cutting did not affect systolic function (P > 0.05) but significantly increased overall diastolic compliance (P = 0.009). Greater compliance was seen as trabecular cutting increased (P = 0.002, r2 = 0.435). In the second experiment, significant increases in systolic function (P = 0.048) and diastolic compliance (P = 0.002) were seen after trabecular cutting compared with baseline. In conclusion, trabecular cutting significantly increases diastolic compliance without reducing systolic function.NEW & NOTEWORTHY We postulate that, in mammalian hearts, free-running trabeculae carneae exist to provide tensile support to the left ventricle and minimize diastolic wall stress. Because of hypertrophy and fibrosis of trabeculae in patients with left ventricular hypertrophy, this supportive role can become pathologic, worsening diastolic compliance. We demonstrate a novel operation involving cutting trabeculae as a method to acutely increase diastolic compliance in patients presenting with heart failure and diastolic dysfunction to improve their left ventricle compliance.

Contemporary surgical outcomes of venous tumour thrombectomy managed with intraoperative Doppler ultrasound for kidney cancer.

INTRODUCTION: Radical nephrectomy (RN) with venous tumour thrombectomy (VTT) carries a significant morbidity and mortality risk. Examination of a contemporary single-institution series permits the development of a management algorithm and an audit its results. We report outcomes following the use of intraoperative colour Doppler ultrasound and our surgical pathway. METHODS: We retrospectively reviewed the records of all patients who underwent RN with VTT for kidney cancer between January 1, 2013 and October 1, 2016. Surgical complications, postoperative complications (Clavien-Dindo classification ≥3), 90-day readmission rates, and outcomes are reported. Multivariate linear regression, logistic regression, and Cox proportional hazard modelling were used to identify associations. RESULTS: Fifty-eight patients underwent RN with VTT. Of these, 26 (45%) patients had Mayo Clinic level III or IV thrombus and nineteen required venovenous/cardiopulmonary bypass. Three patients required patch grafting. The median length of hospital stay was eight days and there were 20 major complications. The 30-day readmission rate was 21% and the 90-day mortality rate was 8.9%. In multivariate analysis, low serum albumin and age-adjusted Charlson comorbidity score predicted length of stay. Increased intraoperative blood loss was significantly associated with increasing body mass index, serum creatinine, tumour thrombus level, and a history of significant weight loss >9.1kg. Low serum hematocrit predicted 90-day mortality. CONCLUSIONS: Intraoperative colour Doppler ultrasound is a useful tool and can facilitate caval preservation. Caval grafting can be avoided in most cases. Venovenous bypass can be avoided in many level III cases. Early therapeutic anticoagulation should be instituted with caution.