Long-term outcomes of patients with primary graft dysfunction after cardiac transplantation

OBJECTIVES

The International Society of Heart and Lung Transplantation (ISHLT) criteria for primary graft dysfunction (PGD) after cardiac transplantation have been shown to stratify patient outcomes up to 1 year after transplantation, but scarce data are available regarding outcomes beyond the 1st year. We sought to characterize survival of patients with PGD following cardiac transplantation beyond the 1st year.

METHODS

A retrospective review of consecutive patients undergoing isolated cardiac transplantation at a single centre between 2012 and 2015 was performed. Patients were diagnosed with none, mild, moderate or severe PGD by the ISHLT criteria. Survival was ascertained from the United Network for Organ Sharing database and chart review. Kaplan-Meier curves were plotted to compare survival. The hazard ratio for mortality associated with PGD severity was estimated using Cox-proportional hazards modelling, with a pre-specified conditional survival analysis at 90 days.

RESULTS

A total of 257 consecutive patients underwent cardiac transplantation during the study period, of whom 73 (28%) met ISHLT criteria for PGD: 43 (17%) mild, 12 (5%) moderate and 18 (7%) severe. Patients with moderate or severe PGD had decreased survival up to 5 years after transplantation (log-rank P < 0.001). Landmark analyses demonstrated that patients with moderate or severe PGD were at increased risk of mortality during the first 90-days after transplantation as compared to those with none or mild PGD [hazard ratio (95% confidence interval) 18.9 (7.1-50.5); P < 0.001], but this hazard did not persist beyond 90-days in survivors (P = 0.64).

CONCLUSIONS

A diagnosis of moderate or severe PGD is associated with increased mortality up to 5 years after cardiac transplantation. However, patients with moderate or severe PGD who survive to post-transplantation day 90 are no longer at increased risk for mortality as compared to those with none or mild PGD.

ALLY in fighting COVID-19: magnitude of albumin decline and lymphopenia (ALLY) predict progression to critical disease

The global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic leading to coronavirus disease 2019 (COVID-19) is straining hospitals. Judicious resource allocation is paramount but difficult due to the unpredictable disease course. Once hospitalized, discerning which patients may progress to critical disease would be valuable for resource planning. Medical records were reviewed for consecutive hospitalized patients with COVID-19 in a large healthcare system in Texas. The main outcome was progression to critical disease within 10 days from admission. Albumin trends from admission to 7 days were analyzed using mixed-effects models, and progression to critical disease was modeled by multivariable logistic regression of laboratory results. Risk models were evaluated in an independent group. Of 153 non-critical patients, 28 (18%) progressed to critical disease. The rate of decrease in mean baseline-corrected (Δ) albumin was -0.08 g/dL/day (95% CI -0.11 to -0.04; p<0.001) or four times faster, in those who progressed compared with those who did not progress. A model of Δ albumin combined with lymphocyte percentage predicting progression to critical disease was validated in 60 separate patients (sensitivity, 0.70; specificity, 0.74). ALLY (delta albumin and lymphocyte percentage) is a simple tool to identify patients with COVID-19 at higher risk of disease progression when: (1) a 0.9 g/dL or greater albumin drop from baseline within 5 days of admission or (2) baseline lymphocyte of ≤10% is observed. The ALLY tool identified >70% of hospitalized cases that progressed to critical COVID-19 disease. We recommend prospectively tracking albumin. This is a globally applicable tool for all healthcare systems.

Trends in post-heart transplant biopsies for graft rejection versus nonrejection

With alternatives such as gene profiling available for surveillance after orthotopic heart transplantation, we sought to evaluate the utilization of endomyocardial biopsies (EMBs) for hospitalized patients after heart transplantation. Surveillance EMBs in patients with and without complications were evaluated from the 2004 to 2014 National Inpatient Sample. Over the study period, there was no significant change in the number of EMB procedures performed (P = 0.44). Of 37,955 EMBs, 2283 (6%) were in the setting of graft complications, while 35,672 EMBs were not related to graft complications. EMBs in graft complications did not show a significant increase in length of stay over time (P = 0.06), but had a significant increase in cost over time (P = 0.001). However, those with graft complications had an average of a 5-day longer length of stay (P < 0.001) and costs that were $88,816 (P < 0.001) more expensive compared with those without graft complications. In conclusion, the vast majority of in-hospital EMBs were not related to heart transplantation complications. Nevertheless, EMB hospitalizations with graft complications showed significantly greater length of stay and cost. With the COVID-19 pandemic, it seems more effective to use minimal-contact health surveillance methods rather than invasive EMBs.

The utility of boxing for cardiac prehabilitation

A 56-year-old man with end-stage heart failure performed a 4-week, symptom-limited, progressive inpatient cardiac prehabilitation program while confined to the cardiovascular intensive care unit awaiting heart transplantation. Mobility was limited by an acute gout flare and multiple central venous access lines. He received a tailored prescription of intermittent boxing, supervised hallway ambulation, stair training, and golfing on a putting green on four consecutive weekdays and was encouraged to mobilize with nursing on the remaining days. The patient progressed and by the last week demonstrated increased activity tolerance. He had a successful transplant after 40 days in the intensive care unit and was discharged with stamina sufficient to participate in outpatient cardiac rehabilitation, demonstrating the value, safety, and feasibility of an individualized inpatient cardiac prehabilitation program for patients with advanced cardiac disease medically confined to the intensive care unit.

Advanced heart failure with reduced ejection fraction

Patients suffering advanced heart failure with reduced ejection fraction (HFrEF) account for a large portion of patients admitted to hospitals worldwide. Mortality and 30-day readmission rates for HFrEF are now a focus of value-based payment models, making management of this disease a priority for hospitals, physicians, and payers alike. Angiotensin-converting enzyme inhibitors have been the cornerstone of therapy for decades. However, with treatment, the prognosis for patients with advanced HFrEF remains poor. Fortunately, advances in medical therapy and mechanical support offer some patients improvement in both survival and quality of life. We review advances in short- and long-term mechanical support and explore changes to organ allocation for cardiac transplantation. In addition, we provide a guide to facilitate appropriate referral to an advanced heart failure team.

Cardiogenic Shock in Patients with Advanced Chronic Heart Failure

Patients with end-stage heart failure (HF) who have failed optimal medical therapy provide a unique set of challenges compared to the more prevalent population of patients with cardiogenic shock (CS) due to ST-segment elevation myocardial infarction. Progression from "preshock" into a refractory state of CS is associated with a dismal outcome due to difficulties with the patient's recognition, response to interventions, and candidacy for salvage options. Challenges include heterogeneity of CS (eg, different phenotypes, etiologies, duration, acuity of onset, hemodynamics, end-organ effects), lack of a universal definition of CS that is applicable to this patient population, and blunted hemodynamic response given the patient's prolonged compensatory state. Individuals with advanced HF in CS require a multidisciplinary team-based assessment regarding when to escalate from medical therapy into temporary mechanical circulatory support, and they need an eligibility evaluation to determine their candidacy for advanced therapy. In this review, we discuss the definition and clinical phenotypes of CS, classification of CS in advanced HF patients, the utility of temporary mechanical circulatory support, and the role of the CS team.

Usefulness of Total 12-Lead QRS Voltage as a Clue to Diagnosis of Patients With Cardiac Sarcoidosis Severe Enough to Warrant Orthotopic Heart Transplant

Importance

Severe heart failure caused by cardiac sarcoidosis is difficult to diagnosis without biopsy.

Objective

To assess whether total electrocardiographic 12-lead QRS voltage may be a clue to diagnosis.

Design, Setting, Participants

Case-series study with cases collected at Baylor University Medical Center at Dallas, Dallas, Texas, from January 13, 2005, to January 24, 2017. The clinical records of 16 patients with severe heart failure caused by cardiac sarcoidosis were studied. Examination of total 12-lead electrocardiographic QRS voltage (peak of the R wave to the nadir of either the Q or S wave, whichever was deeper) was performed prior to orthotopic heart transplant (OHT). Gross and microscopic pathologic specimens of the native hearts were studied.

Main Outcomes and Measures

The primary outcome was to correlate the total 12-lead QRS voltage measurement with various morphologic features in the native diseased heart.

Results

The 16-patient study group consisted of 8 men and 8 women; 12 (75%) were white and 4 (25%) were black. At the time of OHT, patient age ranged from 50 to 67 years (mean, 57 years). Cardiac sarcoidosis was diagnosed by pre-OHT biopsy results in 2 (13%) patients and by examination of the native heart after OHT in 14 (87%) patients. Total nonpaced 12-lead QRS voltage mean was 117 mm (range, 52-155 mm) for 8 patients and total paced 12-lead QRS voltage was 90 mm (range, 67-161 mm) for 12 patients. These low mean values were similar to those of patients with carcinoid heart disease (mean [SD], 105 [40] mm), cardiac amyloidosis (104 [35] mm), and severe cardiac adiposity (120 [31] mm) studied at necropsy or after OHT. In contrast, mean (SD) values were 323 (109) mm in patients with massive cardiomegaly, 257 mm in patients with severe aortic stenosis, 272 (86) mm in patients with severe pure aortic regurgitation, 220 (67) mm in patients with severe pure mitral regurgitation, 197 (64) mm in patients with hypertrophic cardiomyopathy, and 153 (40) mm in patients with idiopathic dilated cardiomyopathy.

Conclusions and Relevance

Most patients diagnosed with cardiac sarcoidosis causing severe heart failure and warranting OHT had low total 12-lead QRS voltage measurements despite having native hearts of increased weight. This finding may provide a clue to the diagnosis of this disease.

Outcomes of orthotopic heart transplantation and left ventricular assist device in patients aged 65 years or more with end-stage heart failure

Age has traditionally been a limiting factor for advanced heart failure (HF) therapies. Orthotopic heart transplantation (OHT) age guidelines have become less restrictive, and left ventricular assist devices (LVADs) are increasingly utilized as destination therapy for patients ≥65 years. Although indications differ, we assessed outcomes for both modalities in this older population. We reviewed charts of consecutive advanced HF therapy recipients aged ≥65 years at our center from 2012 to 2016. Of 118 patients evaluated, 46 (39%) received an LVAD and 72 (61%) received OHT. Gender, body mass index, and rate of prior sternotomy were similar between groups; OHT recipients were younger, less likely to have diabetes mellitus, and more likely to have HF due to ischemic etiology. Forty-six percent of patients receiving LVADs were urgent need (Interagency Registry for Mechanically Assisted Circulatory Support [INTERMACS] profile 1-2), compared to 29% of patients receiving OHT (United Network for Organ Sharing 1A criteria; P = 0.068). OHT recipients had shorter lengths of stay and better 1-year survival compared to LVAD recipients. Although many centers do not offer advanced HF therapy to patients aged ≥65 years, our results indicate that age alone should not be prohibitive for advanced HF therapy, particularly OHT.

Effect of Progressive Left Ventricular Dilatation on Degree of Mitral Regurgitation Secondary to Mitral Valve Prolapse

Described herein is a 71-year-old man who at age 61 was found by echocardiogram to have severe mitral regurgitation (MR) from mitral valve prolapse. During the subsequent 9 years the MR progressively lessened as his left ventricular cavity dilated and his ejection fraction progressively fell such that just before orthotopic heart transplantation the degree of MR was no longer severe, and the prolapse of the mitral leaflets had disappeared. This report describes this unique patient.

Morphological and Functional Characteristics of the Right Ventricle Functioning as a Systemic Ventricle for Decades After an Atrial Switch Procedure for Complete Transposition of the Great Arteries

Described herein are certain clinical and cardiac morphologic findings in 4 adults with complete transposition of the great arteries who underwent the Mustard procedure in the newborn period or in childhood and each lived >30 years thereafter before either having orthotopic heart transplantation (3 patients) or dying while awaiting orthotopic heart transplantation. Compared with the wall of the left ventricle, the wall of the right ventricle (the systemic one) was much thicker, the myofibers much larger, and either grossly-visible or microscopic-sized scars were present in its wall. Additionally, some intramural coronary arteries in the right ventricular wall were numerous, large, had thick walls, and often narrowed lumens. That the Mustard operation provided the necessary time for the right ventricle (the systemic one) to develop to its fullest is a tribute to this procedure.

SCAI clinical expert consensus statement on the classification of cardiogenic shock: This document was endorsed by the American College of Cardiology (ACC), the American Heart Association (AHA), the Society of Critical Care Medicine (SCCM), and the Society of Thoracic Surgeons (STS) in April 2019

BACKGROUND

The outcome of cardiogenic shock complicating myocardial infarction has not appreciably changed in the last 30 years despite the development of various percutaneous mechanical circulatory support options. It is clear that there are varying degrees of cardiogenic shock but there is no robust classification scheme to categorize this disease state.

METHODS

A multidisciplinary group of experts convened by the Society for Cardiovascular Angiography and Interventions was assembled to derive a proposed classification schema for cardiogenic shock. Representatives from cardiology (interventional, advanced heart failure, noninvasive), emergency medicine, critical care, and cardiac nursing all collaborated to develop the proposed schema.

RESULTS

A system describing stages of cardiogenic shock from A to E was developed. Stage A is "at risk" for cardiogenic shock, stage B is "beginning" shock, stage C is "classic" cardiogenic shock, stage D is "deteriorating", and E is "extremis". The difference between stages B and C is the presence of hypoperfusion which is present in stages C and higher. Stage D implies that the initial set of interventions chosen have not restored stability and adequate perfusion despite at least 30 minutes of observation and stage E is the patient in extremis, highly unstable, often with cardiovascular collapse.

CONCLUSION

This proposed classification system is simple, clinically applicable across the care spectrum from pre-hospital providers to intensive care staff but will require future validation studies to assess its utility and potential prognostic implications.

Development and validation of a multiplex fluorescent microsphere immunoassay assay for detection of porcine cytokines

Cytokines are cell signalling proteins that mediate a number of different physiological responses. The accurate measurement of cytokine profiles is important for a variety of diagnostic and prognostic scenarios in relation to animal health and welfare. Simultaneous quantification of cytokine profiles in a single sample is now possible using fluorescent microsphere immunoassays (FMIA). We describe the development and validation of a novel multiplex assay using the Bio-Plex® 200 system to quantify cytokines in five different porcine tissues (brain, placenta, synovial tissue and fluid, plasma). The cytokine profiles are both tissue, and research hypothesis, -dependent but include Interleukin-1beta (IL-1β), Interleukin-4 (IL-4), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10) and Tumor necrosis factor (TNF-α).

This methods paper is reported in two parts: the development of a FMIA for porcine tissues and validation of pre-treatment for optimal cytokine recovery in porcine brain, placenta, synovial tissue and plasma. Validation steps are critical in ensuring an assay is suitable for novel sample types.

This technique advances traditional ELISAs by:

•

FMIA provides insight into the profiles of multiple porcine cytokines in certain situations (e.g. disease, parturition).

•

Use of the Bio-Plex® 200 system to investigate novel sample types, including brain, placenta and synovial tissue.

•

Multiplexing utilises a fraction of the sample volume compared with multiple ELISAs.

Predictors and impact of right heart failure severity following left ventricular assist device implantation

Background

Right heart failure (RHF) is a well-known consequence of left ventricular assist device (LVAD) placement, and has been linked to negative surgical outcomes. However, little is known regarding risk factors associated with RHF. This article delineates pre- and intra-operative risk factors for RHF following LVAD implantation and demonstrates the effect of RHF severity on key surgical outcomes.

Methods

We performed a retrospective analysis of consecutive LVAD patients treated at our center between 2008 and 2016. RHF was categorized using the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) definition of none/mild, moderate, severe, and acute-severe. We constructed a predictive model using multivariable logistic regression and performed a competing risks analysis for survival stratified by RHF severity.

Results

Of 202 subjects, 52 (25.7%) developed moderate or worse RHF. Cardiopulmonary bypass (CPB) time and nadir hematocrit contributed jointly to the model of RHF severity (moderate or worse vs. none/mild; area under the curve =0.77). Postoperative length of stay (LOS) was shortest in the non/mild group and longest in the acute-severe group (median 13 vs. 29.5 days; P<0.001). Stage 2/3 acute kidney injury (range, 26-57%, P=0.002), respiratory failure (13-94%, P<0.001), stroke (0-32%, P=0.02), and 1-year mortality (19-64%, P=0.002) differed by severity. Those with acute-severe RHF had 5.4 [95% confidence interval (CI), 2.5-11.8] times the risk of 1-year mortality compared to those who did not have RHF.

Conclusions

RHF remains a postoperative threat and is associated with worsened surgical outcomes. Ongoing research will reveal further opportunities to mitigate RHF post-LVAD.

Patient "Activation" of Patients Referred for Advanced Heart Failure Therapy

Advanced heart failure (HF) is a devastating chronic illness requiring complex treatment regimens and patient engagement. Having the information, motivation, and skills to live with a medical condition are conceptualized by the term, "activation." Patients referred for advanced HF therapy and their unpaid family caregiver were invited to participate in this study by completing the 10-item patient activation measure (PAM) questionnaire. Anxiety and depression were assessed via the hospital anxiety and depression scale. We compared activation, anxiety, and depression between those selected versus not selected for advanced HF therapy (left ventricular assist device or heart transplantation). We analyzed those who subsequently underwent advanced HF therapy in regards to activation and 1-year survival. There were 133 (68%) patients selected for therapy. Neither depression nor anxiety differed by selection status, but PAM levels did (p = 0.02). Those not selected for therapy were approximately 4 times more likely to have lower activation than those who were selected (8% vs 2%). Of the 133 selected patients, 110 (84%) subsequently underwent advanced HF therapy and 15 (14%) of those died within 1 year. Survival was independent of baseline anxiety (p = 0.92) and depression (p = 0.70), as well as patient and caregiver PAM (p = 0.50 and 0.77, respectively). In conclusion, patients with higher activation were more likely to be selected for advanced HF therapy.

The Mitral Valve 16 Months After Operative Insertion of the Alfieri Stitch

We describe considerable fibrous thickening of the mitral leaflets 16 months after insertion of an Alfieri stitch in a previously anatomically normal but functionally regurgitant mitral valve. Whether this type of mitral thickening will occur after percutaneous insertion of the mitral clip for pure mitral regurgitation remains to be determined.

Outcomes of Moderate-to-Severe Acute Kidney Injury following Left Ventricular Assist Device Implantation

BACKGROUND

Although acute kidney injury (AKI) is a common complication following cardiac surgery, less is known about the occurrence and consequences of moderate/severe AKI following left ventricular assist device (LVAD) implantation.

METHODS

All patients who had an LVAD implanted at our center from 2008 to 2016 were reviewed to determine the incidence of, and risk factors for, moderate/severe (stage 2/3) AKI and to compare postoperative complications and mortality rates between those with and those without moderate/severe AKI.

RESULTS

Of 246 patients, 68 (28%) developed moderate/severe AKI. A multivariable logistic regression comprising body mass index and prior sternotomy had fair predictive ability (area under the curve = 0.71). A 1-unit increase in body mass index increased the risk of moderate/severe AKI by 7% (odds ratio = 1.07; 95% confidence interval: 1.03-1.11); a prior sternotomy increased the risk more than 3-fold (odds ratio = 3.4; 95% confidence interval: 1.84-6.43). The group of patients with moderate/severe AKI had higher rates of respiratory failure and death than the group of patients with mild/no AKI. Patients with moderate/severe AKI were at 3.2 (95% confidence interval: 1.2-8.2) times the risk of 30-day mortality compared to those without. Even after adjusting for age and Interagency Registry for Mechanically Assisted Circulatory Support profile, those with moderate/severe AKI had 1.75 (95% confidence interval: 1.03-3.0) times the risk of 1-year mortality compared to those without.

DISCUSSION

Risk-stratifying patients prior to LVAD placement in regard to AKI development may be a step toward improving surgical outcomes.

Cardiac catheterization and percutaneous intervention procedures on extracorporeal membrane oxygenation support

Extracorporeal membrane oxygenation (ECMO) is used to support critically ill patients when conventional therapies have failed. ECMO has been available for four decades and has gained use as a rescue therapy in severe refractory hypoxic disorders and in patients with refractory cardiogenic shock (RCS). Over recent years, several percutaneous cardiac interventions and implant devices have been developed that are now used frequently in conjunction with ECMO in order to maintain organ perfusion. Here, we review the literature on VA-ECMO cannulation location, the use of VA-ECMO in interventions (e.g., coronary interventions and structural heart interventions) and percutaneous cardiac device implantation in VA-ECMO recipients with RCS.

Relation of Vasoplegia in the Absence of Primary Graft Dysfunction to Mortality Following Cardiac Transplantation

Vasoplegia following cardiac transplantation is associated with increased morbidity and mortality. Previous studies have not accounted for primary graft dysfunction (PGD). The definition of vasoplegia is based on pressor requirement at 48 hours, many PGD parameters may have normalized after the initial 24 hours on inotropes. We surmised that the purported negative effects of vasoplegia following transplantation may in part be driven by PGD. We reviewed 240 consecutive adult cardiac transplants at our center between 2012 and 2016. The severity of vasoplegia was evaluated as a risk factor for 1-year survival, and the analysis was repeated for the subgroup of 177 patients who did not develop PGD. Overall, 63 (26%) of patients developed mild, moderate, or severe PGD. In those without PGD, vasoplegia was associated with length of stay but not with short- or long-term mortality. Moderate and/or severe vasoplegia occurred in 35 (15%) patients and was associated with higher short-term mortality, length of stay, and PGD. Multivariate logistic regression identified body mass index ≥35 kg/m², left ventricular assist device before transplantation, and use of extracorporeal membrane oxygenation as joint risk factors for vasoplegia. In patients without PGD, only left ventricular assist device before transplantation was associated with vasoplegia. In conclusion, our results show that, in the sizeable subgroup of patients with no signs of PGD, vasoplegia had a much more modest impact on post-transplant morbidity and no significant effect on 1- and 3-year survival. This suggests that PGD may be a confounder when assessing vasoplegia as a risk factor for adverse outcomes.