Publications by authors named "David W Markham"

Article Synopsis
  • Ventricular arrhythmias (VAs) like ventricular tachycardia and ventricular fibrillation pose serious treatment challenges with high risks of morbidity and mortality, particularly in patients unresponsive to standard therapies.
  • This study examined the safety and effectiveness of CT-guided left stellate ganglion cryoneurolysis (SGC) in these refractory VA patients across two hospitals, involving 17 patients with a notable reduction in defibrillation events after the procedure.
  • Results showed that 82% of patients were free from defibrillation 24 hours post-procedure, with no serious adverse effects reported, highlighting the potential of SGC as a beneficial alternative treatment strategy for refractory VAs.
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Background "Financial toxicity" is a concern for patients, but little is known about how patients consider out-of-pocket cost in decisions. Sacubitril-valsartan provides a contemporary scenario to understand financial toxicity. It is guideline recommended for heart failure with reduced ejection fraction, yet out-of-pocket costs can be considerable.

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Objectives: The aim of this study was to prospectively evaluate the impact of blood pressure management on stroke rates in patients receiving the HeartWare HVAD System.

Background: The ENDURANCE trial demonstrated noninferiority of the HeartWare HVAD System versus control (HeartMate II) in patients with advanced heart failure ineligible for heart transplantation. However, stroke was more common in HVAD subjects.

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Objectives: This study sought to estimate the rate of progression to Stage D heart failure (HF) among outpatients with Stage C HF and to identify risk factors for progression.

Background: The pool of patients who may be candidates for advanced HF therapies is growing.

Methods: We estimated 3-year progression to clinically determined Stage D HF and competing mortality among 964 outpatients with Stage C heart failure with reduced ejection fraction (HFrEF), where ejection fraction is ≤40%.

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Background: Peripartum cardiomyopathy (PPCM) remains a major cause of maternal morbidity and mortality.

Objectives: This study sought to prospectively evaluate recovery of the left ventricular ejection fraction (LVEF) and clinical outcomes in the multicenter IPAC (Investigations of Pregnancy Associated Cardiomyopathy) study.

Methods: We enrolled and followed 100 women with PPCM through 1 year post-partum.

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Background: Several clinical prediction schemes for right ventricular failure (RVF) risk after left ventricular assist device (LVAD) implantation have been developed in both the pulsatile- and continuous-flow LVAD eras. The performance of these models has not been evaluated systematically in a continuous-flow LVAD cohort.

Methods: We evaluated 6 clinical RVF prediction models (Michigan, Penn, Utah, Kormos et al, CRITT, Pittsburgh Decision Tree) in 116 patients (age 51 ± 13 years; 41.

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The past decade has seen remarkable gains for outcomes in peripartum cardiomyopathy (PPCM), one of the leading causes of maternal mortality and morbidity in the USA and many other countries, including the high-incidence areas of Haiti and South Africa. This review article emphasizes the importance of continuing the process of increasing awareness of PPCM and presents details of this evolving picture, including important discoveries that point the way to full recovery for almost all PPCM subjects. In addition, new interventions will be highlighted, which may facilitate recovery.

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Background: Insertion of a left ventricular assist device (LVAD) is an accepted therapy for advanced heart failure patients. However, the effects on end-organ perfusion, including cerebral autoregulation, are unclear in the presence of reduced pulsatility. Therefore, the objective of this study was to determine whether cerebral autoregulation is impaired in patients with continuous-flow (CF) LVADs.

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Background: Some cardiac transplant programs may upgrade listed patients to United Network for Organ Sharing (UNOS) 1A-status during the holidays. Whether more transplants actually occur during holidays is unknown.

Methods: We assessed rates of single-organ heart transplantation from 2001 to 2010 for recipients age ≥18 yr using the UNOS database.

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Background: A noninvasive biomarker that could accurately diagnose acute rejection (AR) in heart transplant recipients could obviate the need for surveillance endomyocardial biopsies. We assessed the performance metrics of a novel high-sensitivity cardiac troponin I (cTnI) assay for this purpose.

Methods And Results: Stored serum samples were retrospectively matched to endomyocardial biopsies in 98 cardiac transplant recipients, who survived ≥3 months after transplant.

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Objectives: This study sought to examine the frequency and hemodynamic correlates of shortness of breath when bending forward, a symptom we have termed "bendopnea."

Background: Many heart failure patients describe bendopnea such as when putting on their shoes. This symptom has not previously been characterized.

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Sirolimus is used in cardiac transplant recipients to prevent rejection, progression of cardiac allograft vasculopathy, and renal dysfunction. However, sirolimus has many potential side effects and its tolerability when used outside of clinical trials is not well established. We describe a decade of experience with sirolimus in cardiac transplant recipients at our institution.

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Background: Although right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) are correlated in heart failure, in a sizeable minority of patients, the RAP and PCWP are not tightly coupled. The basis of this variability in the RAP/PCWP ratio, and whether it conveys prognostic value, is not known.

Methods And Results: We analyzed the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial database.

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Background: Left ventricular assist devices (LVADs) are now widely accepted as an option for patients with advanced heart failure. First-generation devices were pulsatile, but they had poor longevity and durability. Newer generation devices are nonpulsatile and more durable, but remain associated with an increased risk of stroke and hypertension.

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Background: Left ventricular assist device (LVAD) support as bridge to recovery (BTR) is uncommon for subjects with chronic heart failure. Myocardial recovery is more evident in recent onset nonischemic cardiomyopathy (ROCM); however, the prevalence of BTR in this subset has not been addressed.

Methods And Results: We examined the use of LVAD support for subjects with ROCM in the Intervention in Myocarditis and Acute Cardiomyopathy 2 (IMAC2) study.

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Background: Guidelines recommend that patients with new-onset systolic heart failure (HF) receive a trial of medical therapy before an implantable cardiac defibrillator (ICD). This strategy allows for improvement of left ventricular ejection fraction (LVEF), thereby avoiding an ICD, but exposes patients to risk of potentially preventable sudden cardiac death during the trial of medical therapy.

Methods: We reviewed a consecutive series of patients with HF of <6 months duration with a severely depressed LVEF (<30%) evaluated in a HF clinic (N = 224).

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Background: Given the potential for recovery in recent onset nonischemic cardiomyopathy (ROCM), the timing and need for implantable cardioverter-defibrillator (ICDs) remains controversial. We examined the utilization of ICDs and the impact on survival for subjects with ROCM.

Methods And Results: An National Heart, Lung, and Blood Institute sponsored registry enrolled 373 subjects with ROCM, all with a left ventricular ejection fraction (LVEF) ≤0.

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Aims: Left atrial (LA) structural and functional abnormalities may be subclinical phenotypes, which identify individuals at increased risk of adverse outcomes.

Methods And Results: Maximum LA volume (LAmax) and LA emptying fraction (LAEF) were measured via cardiac magnetic resonance imaging in 1802 participants in the Dallas Heart Study. The associations of LAEF and LAmax indexed to body surface area (LAmax/BSA) with traditional risk factors, natriuretic peptide levels, and left ventricular (LV) structure [end-diastolic volume (EDV) and concentricity(0.

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Sirolimus is an immunosuppressive agent increasingly used in cardiac transplant recipients in the setting of allograft vasculopathy or worsening renal function. Recently, sirolimus has been associated with increased risk of venous thromboembolism (VTE) in lung transplant recipients. To investigate whether this association is also present in cardiac transplant recipients, we retrospectively reviewed the charts of 67 cardiac transplant recipients whose immunosuppressive regimen included sirolimus and 134 matched cardiac transplant recipients whose regimen did not include sirolimus.

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The term New York Heart Association (NYHA) class IIIB has been used increasingly in clinical medicine, including as an inclusion criteria for many clinical trials assessing left ventricular assist devices (LVADs). Indeed, NYHA class IIIB is incorporated in the Food and Drug Administration's approved indication for the Heartmate II. However, on review of the medical literature, we found that there is no consensus definition of NYHA class IIIB.

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Whether concentric left ventricular (LV) hypertrophy (LVH) is a common precursor to depressed LV ejection fraction (EF) in humans is uncertain. From 1992 through 1994, 555 patients at our institution underwent echocardiography and had LVH (posterior or septal wall thickness ≥1.3 cm or concentric LVH noted) and normal LVEF.

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Background: Identifying asymptomatic individuals with American Heart Association/American College of Cardiology stage B heart failure (HF) in the population is an important step to prevent the development of symptomatic HF. The comparative utility of 2 screening strategies (biomarkers vs risk scores) in identifying prevalent stage B HF is unknown.

Methods: Participants 30 to 65 years old without symptomatic HF in the Dallas Heart Study who had a cardiac magnetic resonance imaging were included (n = 2,277).

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