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An 81-year-old male with a history of coronary artery disease, hypertension, paroxysmal atrial fibrillation and chronic kidney disease presents with asymptomatic bradycardia. Examination was notable for an early diastolic heart sound. 12-lead electrocardiogram revealed sinus bradycardia with a markedly prolonged PR interval and second-degree atrioventricular block, type I Mobitz. We review the differential diagnosis of early diastolic heart sounds and present a case of Wenckebach associated with a variable early diastolic sound on physical exam.

Fractional flow reserve (FFR) determines the functional significance of epicardial stenoses assuming negligible venous pressure (Pv) and microvascular resistance. However, these assumptions may be invalid in end-stage liver disease (ESLD) because of fluctuating Pv and vasodilation. Accordingly, all patients with ESLD who underwent right-sided cardiac catheterization and coronary angiography with FFR as part of their orthotopic liver transplantation evaluation between 2013 and 2018 were included in the present study. Resting mean distal coronary pressure (Pd)/mean aortic pressure (Pa), FFR, and Pv were measured. FFR accounting for Pv (FFR - Pv) was defined as (Pd - Pv)/(Pa - Pv). The hyperemic effect of adenosine was defined as resting Pd/Pa - FFR. The primary outcome was all-cause mortality at 1 year. In 42 patients with ESLD, 49 stenoses were interrogated by FFR (90% were

Introduction: Randomized trials have demonstrated the safety and efficacy of one month of dual antiplatelet therapy (DAPT) after placement of drug-eluting stents in patients with high bleeding risk. Patients with end-stage liver disease (ESLD) are underrepresented in these trials. Patients who undergo percutaneous coronary intervention (PCI) in preparation for orthotopic liver transplantation (OLT) exhibit a high incidence of bleeding complications on DAPT. The rates of bleeding versus thrombotic complications in ESLD patients placed on DAPT following PCI are poorly described. Methods: We retrospectively collected data from 61 patients who were evaluated for OLT between 2016 and 2019 and underwent PCI prior to listing. Bleeding events were classified using the Bleeding Academic Research Consortium (BARC) definitions and included if the following criteria were met: events occurred in the setting of DAPT, were non-procedural in etiology, and occurred during the time following PCI and prior to OLT. Ischemic complications were evaluated by the incidence of myocardial infarction (MI), stent thrombosis, in-stent restenosis (>50%) and all-cause mortality at 1 year follow-up. Results: A total of 55/61 patients (90%) were placed on DAPT following PCI. Among them, 21/55 patients (38%) bled while taking DAPT, including 15 patients (27%) with BARC types 3-5 first-time bleeding events and 10 patients (18%) requiring early discontinuation of therapy. The median time to first bleeding event was 8 days (range 1 to 477 days, 85 th percentile 17 days). Among ischemic complications, MI occurred in 11/55 patients (20%) however only one patient had a type 1 MI with the remaining being type 2 in etiology. There were no episodes of stent thrombosis and 2 episodes of in-stent restenosis during the 1 year follow-up. A total of 12/55 patients (22%) went on to receive OLT and 18/55 (33%) passed away by 1 year post-PCI. Conclusions: Patients with ESLD exhibit a high rate of clinically significant bleeding on DAPT when compared to overall thrombotic events. The majority of bleeds occurred within the first month after PCI. These findings illustrate the need for larger studies to assess the safety of single instead of dual antiplatelet therapy in patients with ESLD who receive PCI.

Guidelines to evaluate patients for coronary artery disease (CAD) during preoperative evaluation for orthotopic liver transplantation (OLT) are conflicting. Cardiac catheterization is not without risk in patients with end-stage liver disease. No study to date has looked at the utility of non-electrocardiogram-gated chest computed tomography (CT) in the preliver transplant population. Our hypothesis was that coronary artery calcium scores (CACSs) from chest CT scans ordered during the liver transplant workup can identify patients who would benefit from invasive angiography. Nine hundred and fifty-three patients who underwent coronary angiography as part of their OLT workup were considered. Charts were randomly selected and reviewed for the presence of a chest CT performed before coronary angiography during the OLT workup. Agatston and Weston scores were calculated. CACS results were compared with coronary angiography findings. Nine of 54 patients were found to have obstructive CAD by angiography. Receiver-operating characteristic analysis demonstrated that an Agatston score of 251 and a Weston score of 6 maximized sensitivity and specificity for detection of obstructive coronary disease. An Agatston score

Adverse cardiovascular events after liver transplantation (LT) are relatively common and are a significant source of early mortality. Although new-onset systolic dysfunction after LT is a reported phenomenon, there is little data regarding its incidence, risk factors, and outcomes.This single-center retrospective study included all adult patients from January 2002 to March 2015 with deceased-donor LT and available preoperative transthoracic echocardiograms (TTEs). In total, 1,760 patients were included in the study, 602 (34.2%) of whom had a postoperative TTE. The primary end point was development of new-onset cardiomyopathy, defined as a new left ventricular ejection fraction (LVEF) of

A 58-year-old woman with a history of Bentall aortic graft and bioprosthetic aortic valve replacement 3 months prior to admission, presented with headache and fever. Imaging yielded a large obstructive filling defect in the ascending aorta, a subarachnoid hemorrhage, and a mycotic aneurysm. Intraoperative specimens grew Aspergillus fumigatus, and despite aggressive measures the patient died. Aspergillus infections of prosthetic vascular grafts are rare surgical complications and are difficult to diagnose given the low incidence of positive microbiology cultures and the long median time between surgery and diagnosis. Treatment has consisted of antifungal and surgical treatment, although mortality remains high.

Patients with end-stage liver disease (ESLD) who also have underlying coronary artery disease (CAD) may be at increased risk for undergoing hemodynamically challenging orthotopic liver transplantation. Noninvasive single-photon emission computed tomographic (SPECT) imaging is often used to determine whether a patient with ESLD has unsuspected CAD. The objective of this study was to determine the accuracy of SPECT imaging for detection of CAD in patients with ESLD. Patients with ESLD who underwent coronary angiography and SPECT imaging before orthotopic liver transplantation were analyzed retrospectively. The predictive accuracy of clinical risk factors was calculated and compared to the results of SPECT imaging. There were 473 SPECT imaging studies. Adenosine SPECT imaging had a sensitivity of 62%, specificity of 82%, positive predictive value of 30%, and negative predictive value of 95% for diagnosing severe CAD. Regadenoson SPECT imaging had a sensitivity of 35%, specificity of 88%, positive predictive value of 23%, and negative predictive value of 93% for diagnosing severe CAD. The accuracy of a standard risk factor analysis showed no statistical difference in predicting CAD compared with adenosine (sensitivity McNemar's p = 0.48, specificity McNemar's p = 1.00) or regadenoson (sensitivity McNemar's p = 0.77, specificity McNemar's p = 1.00) SPECT studies. In conclusion, the 2 pharmaceutical agents had low sensitivity but high specificity for diagnosing CAD. However, because the sensitivity of the test is low, the chances of missing patients with ESLD with CAD is high, making SPECT imaging an inaccurate screening test. A standard risk factor analysis as a predictor for CAD in patients with ESLD is less expensive, has no radiation exposure, and is as accurate as SPECT imaging.

Background: Preoperative risk assessment in liver transplant (LT) candidates, particularly related to cardiac risk, is an area of intense interest for transplant clinicians. Various cardiac testing methods are employed by transplant centers to characterize cardiac risk. Serum troponin is an established method for the detection of myocardial injury in a wide variety of clinical settings. Preoperative troponin screening has been reported to predict postoperative cardiac events and mortality in various surgical patient populations, however, the utility of preoperative troponin to predict posttransplant outcomes in current LT candidate populations requires further investigation. Methods: We performed a prospective blinded study in a cohort of 275 consecutive LT recipients at a single transplant center to determine if preoperative serum troponin I (TnI) was predictive for postoperative 1‐year mortality. Results: Abnormal preoperative TnI levels (>.1 ng/mL) were found in 38 patients (14%). One‐year mortality occurred in 19 patients (7%). There was no significant difference in mortality between patients with normal and abnormal troponin levels. Additionally, we found that there was no significant difference in early postoperative major adverse cardiac events between patient groups. Conclusions: Contrary to previous reports, elevated preoperative TnI was not significantly predictive of posttransplant mortality in LT recipients at our institution. [ABSTRACT FROM AUTHOR]

To delineate the role of mitochondrial [K.sup.+] fluxes in cardioprotection, we investigated the effect of extramitochondrial [K.sup.+] on the ability of mitochondria to support membrane potential ([DELTA][PSI]), regulate matrix volume, consume oxygen, and phosphorylate ADP under conditions mimicking key elements of ischemia-reperfusion. Isolated energized mitochondria responded to ADP addition with depolarization, increased [O.sup.2] consumption, and matrix shrinkage. The time required for full recovery of [DELTA][PSI], signaling the completion of ADP phosphorylation, was used to evaluate the rate of ATP synthesis during repeated ADP pulses. In mitochondria with a decreased ability to support [DELTA][PSI], the rate of ADP phosphorylation was significantly improved by extramitochondrial [K.sup.+] > [Na.sup.+] > [Li.sup.+], especially at higher buffer osmolarity, which promotes matrix shrinkage. [K.sup.+]-induced improvement in [DELTA][PSI] recovery after ADP pulses was accompanied by more rapid and complete matrix volume recovery and enhanced [O.sup.2] consumption. Manipulations expected to affect matrix swelling by regulating [K.sup.+] fluxes or water distribution indicate that matrix volume regulation by external factors becomes increasingly important in mitochondria with decreased ability to support [DELTA][PSI] in the face of a high ADP load. Under these conditions, opening of [K.sup.+] influx pathways improved mitochondrial function and delayed failure. This may be an important factor in the mechanism of diaxozide-induced cardioprotection. mitochondria; matrix swelling; shrinkage; hypoxia; reoxygenation

Fatty acids accumulate during myocardial ischemia and are implicated in ischemia-reperfusion injury and mitochondrial dysfunction. Because functional recovery after ischemia-reperfusion ultimately depends on the ability of the mitochondria to recover membrane potential ([DELTA][[psi].sub.[micro]]), we studied the effects of fatty acids on [DELTA][[psi].sub.[micro]] regulation, cytochrome c release, and [Ca.sup.2+] handling in isolated mitochondria under conditions that mimicked aspects of ischemia-reperfusion. Long-chain but not short-chain free fatty acids caused a progressive and reversible (with BSA) increase in inner membrane leakiness (proton leak), which limited mitochondrial ability to support [DELTA][[psi].sub.[micro]]. In comparison, long-chain activated fatty acids promoted 1) a slower depolarization that was not reversible with BSA, 2) cytochrome c loss that was unrelated to permeability transition pore opening, and 3) inhibition of the adenine nucleotide translocator. Together, these results impaired both mitochondrial ATP production and [Ca.sup.2+] handling. Diazoxide, a selective opener of mitochondrial ATP-dependent potassium ([K.sub.ATP]) channels, partially protected against these effects. These findings indicate that long-chain fatty acid accumulation during ischemia-reperfusion may predispose mitochondria to cytochrome c loss and irreversible injury and identify a novel cardioprotectire action of diazoxide. calcium; adenine nucleotide translocator; membrane potential; cytochrome c; ATP-dependent channel; palmitic acid; palmitoyl-coenzyme A

Korge, Paavo, Henry M. Honda, and James N. Weiss. Regulation of the mitochondrial permeability transition by matrix [C.sup.2+] and voltage during anoxia/reoxygenation. Am J Physiol Cell Physiol 280: C517-C526, 2001.--We studied the interplay between matrix [Ca.sup.2+] concentration ([[Ca.sup.2+]]) and mitochondrial membrane potential ([Delta][Psi]) in regulation of the mitochondrial permeability transition (MPT) during anoxia and reoxygenation. Without [Ca.sup.2+] loading, anoxia caused near-synchronous [Delta][Psi] dissipation, mitochondrial [Ca.sup.2+] efflux, and matrix volume shrinkage when a critically low [PO.sub.2] was reached, which was rapidly reversible upon reoxygenation. These changes were related to electron transport inhibition, not MPT. Cyclosporin A-sensitive MPT did occur when extramitochondrial [[Ca.sup.2+]] was increased to promote significant [Ca.sup.2+] uptake during anoxia, depending on the [Ca.sup.2+] load size and ability to maintain [Delta][Psi]. However, when [[Ca.sup.2+]] was increased after complete [Delta][Psi] dissipation, MPT did not occur until reoxygenation, at which time reactivation of electron transport led to partial [Delta][Psi] regeneration. In the setting of elevated extramitochondrial [Ca.sup.2+], this enhanced matrix [Ca.sup.2+] uptake while promoting MPT because of less than full recovery of [Delta][Psi]. The interplay between [Delta][Psi] and matrix I[Ca.sup.2+]] in accelerating or inhibiting MPT during anoxia/reoxygenation has implications for preventing reoxygenation injury associated with MPT. cardiomyocytes; mitochondrial [Ca.sup.2+] uptake; [Ca.sup.2+] efflux; permeability transition pore

To delineate the role of mitochondrial K+ fluxes in cardioprotection, we investigated the effect of extramitochondrial K+ on the ability of mitochondria to support membrane potential (ΔΦ), regulate matrix volume, consume oxygen, and phosphorylate ADP under conditions mimicking key elements of ischemia-reperfusion. Isolated energized mitochondria responded to ADP addition with depolarization, increased O2 consumption, and matrix shrinkage. The time required for full recovery of ΔΦ. signaling the completion of ADP phosphorylation, was used to evaluate the rate of ATP synthesis during repeated ADP pulses. In mitochondria with a decreased ability to support ΔΦ, the rate of ADP phosphorylation was significantly improved by extramitochondrial K+ > Na+ > Li+, especially at higher buffer osmolarity, which promotes matrix shrinkage. K+-induced improvement in ΔΦ recovery after ADP pulses was accompanied by more rapid and complete matrix volume recovery and enhanced O. consumption. Manipulations expected to affect matrix swelling by regulating K+ fluxes or water distribution indicate that matrix volume regulation by external factors becomes increasingly important in mitochondria with decreased ability to support ΔΦ in the face of a high ADP load. Under these conditions, opening of K+ influx pathways improved mitochondrial function and delayed failure. This may be an important factor in the mechanism of diaxozide-induced cardioprotection. [ABSTRACT FROM AUTHOR]

Mitochondrial permeability transition (MPT) pores have recently been implicated as a potential mediator of myocardial ischemic injury. Nitric oxide (NO) donors induce a poweful late phase of cardioprotection against ischemia-reperfusion injury; however, the cellular mechanisms involved are poorly understood. The role of MPT pores as a target of cardioprotective signaling pathways activated by NO has never been explored in detail. Thus mice were administered the NO donor diethylenetriamine (DETA)/NO (4 doses of 0.1 mg/kg iv each) 24 h before 30 min of coronary artery occlusion followed by 24 h of repeffusion. Infarct size was significantly reduced in DETA/NO-treated ngne (30 ± 2% of risk region in treated mice vs 50 ± 2% in control mice; P < 0.05), which demonstrates powerful cardioprotection. To examine the role of MPT pores, mice were administered atractyloside (Atr; 25 mg/kg iv), which induces adenine nucleotide translocase-dependent MPT, 20 min before ischemia. Atr blocked the infarct-sparing effects of DETA/NO (infarct size, 58 ± 1 vs, 30 ± 2% of risk region in DETA/NO; P < 0.05), whereas Atr alone had no effect. Mitochondria isolated from DETA/NO-treated mice exhibited increased resistance to Ca2+-thdueed swelling by 20 μmol/l CaCl2 or by the higher concentration of 200 μmol/l, which suggests that cardioprotection involves decreased propensity for MPT. Preincubation of mitochondria from control hearts with 30 nmol/l of the pore inhibitor cyclosporin A prevented swelling by 200 μmol/l CaCl2, thereby confirming that Ca2+ induces mitochondrial swelling via MPT. In accordance with the effects on infarct size, administration of Atr to the mice significantly abrogated DETA/NO-induced protection against Ca2+-induced mitochondrial swelling. These phenotypic alterations were associated with an increase in the antiapoptotic protein Bcl-2, which suggests that the underlying mechanisms may involve inhibition of cell death by Bcl-2. These data suggest that a critical process during NO donor-induced cardioprotection is to prevent MPT pore opening potentially via targeting of the adenine nucleotide translocator. [ABSTRACT FROM AUTHOR]

Studies the interplay between matrix calcium concentration and mitochondrial membrane potential in regulation of mitochondrial permeability transition during anoxia and reoxygenation. Effects of anoxia/reoxygenation in mitochondria without calcium loading; Effects of calcium-loading mitochondria before membrane potential dissipation during anoxia.

Aims: In patients with atrial fibrillation (AF) and stroke risk factors, randomized trials have demonstrated that anticoagulation decreases the risk of ischemic stroke. However, all trials to date have excluded patients with significant liver disease, leaving guidelines to extrapolate recommendations. We aim to evaluate the impact of anticoagulation on safety events in patients with AF and cirrhosis., Methods and Results: In this retrospective cohort study, we obtained de-identified health record data to extract anticoagulation strategy, comorbidities, prescriptions, lab values, and procedures for a cohort of patients with cirrhosis who develop AF. After selecting a propensity matched population to match patients with various anticoagulation strategies, we tracked data on outcomes for death, transfusion requirements, hospital and ICU admissions. After propensity score weighting and multivariable adjustment, anticoagulation strategy was associated with increased hospital admission count (OR = 1.74 per admission, P  < .001), binary risk of hospital admission (OR = 1.54, P  = .010) and risk of ICU admission (OR = 1.41, P  = .047). We detected no significant differences in mortality, transfusion of blood products, or average length of stay. Direct oral anticoagulant (DOAC) prescriptions were associated with increased binary risk of hospital admission compared to warfarin prescriptions. In a third comparison, DOAC strategy alone was associated with increased hospital admission count (OR = 1.41 per admission, P  < .001) and binary risk of hospital admission (OR = 1.52, P  = .038) compared to no anticoagulation strategy., Conclusion: Anticoagulation strategy in patients with cirrhosis and AF was associated with increased rate of hospital admission and ICU admission but not associated with increased risk of mortality or transfusion requirement., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Mitochondrial permeability transition (MPT) pores have recently been implicated as a potential mediator of myocardial ischemic injury. Nitric oxide (NO) donors induce a powerful late phase of cardioprotection against ischemia-reperfusion injury; however, the cellular mechanisms involved are poorly understood. The role of MPT pores as a target of cardioprotective signaling pathways activated by NO has never been explored in detail. Thus mice were administered the NO donor diethylenetriamine (DETA)/NO (4 doses of 0.1 mg/kg i.v. each) 24 h before 30 min of coronary artery occlusion followed by 24 h of reperfusion. Infarct size was significantly reduced in DETA/NO-treated mice (30 +/- 2% of risk region in treated mice vs. 50 +/- 2% in control mice; P < 0.05), which demonstrates powerful cardioprotection. To examine the role of MPT pores, mice were administered atractyloside (Atr; 25 mg/kg i.v.), which induces adenine nucleotide translocase-dependent MPT, 20 min before ischemia. Atr blocked the infarct-sparing effects of DETA/NO (infarct size, 58 +/- 1 vs. 30 +/- 2% of risk region in DETA/NO; P < 0.05), whereas Atr alone had no effect. Mitochondria isolated from DETA/NO-treated mice exhibited increased resistance to Ca(2+)-induced swelling by 20 micromol/l CaCl(2) or by the higher concentration of 200 micromol/l, which suggests that cardioprotection involves decreased propensity for MPT. Preincubation of mitochondria from control hearts with 30 nmol/l of the pore inhibitor cyclosporin A prevented swelling by 200 micromol/l CaCl(2), thereby confirming that Ca(2+) induces mitochondrial swelling via MPT. In accordance with the effects on infarct size, administration of Atr to the mice significantly abrogated DETA/NO-induced protection against Ca(2+)-induced mitochondrial swelling. These phenotypic alterations were associated with an increase in the antiapoptotic protein Bcl-2, which suggests that the underlying mechanisms may involve inhibition of cell death by Bcl-2. These data suggest that a critical process during NO donor-induced cardioprotection is to prevent MPT pore opening potentially via targeting of the adenine nucleotide translocator.