Variation of heart transplant rates in the United States during holidays.

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. Patients were stratified by transplantation during holiday (±3 d, n = 2375) and non-holiday periods (n = 16 112). Holidays included Easter/Spring break, Memorial Day, July 4th, Labor Day, Thanksgiving, and Christmas/New Years (winter holidays). Secondary analysis assessing transplant rates across seasons was also completed. RESULTS: Donor and recipient characteristics were similar between groups. Compared with non-holidays, July 4th had higher transplant rates (5.69 vs. 5.09 transplants/d, p = 0.03) while the winter holiday had lower transplant rates (4.50 vs. 5.09 transplants/d, p < 0.01). There was a trend toward lower transplant rates for all holidays compared with non-holidays (p = 0.06). Transplant rates were significantly different across seasons with greater rates in spring and summer (p < 0.01). CONCLUSION: Heart transplant rates were higher during the July 4th and lower during the winter holidays. Although there was a higher likelihood of transplantation during the spring and summer seasons, upgrading patients to 1A status during most holidays may not improve their chances for transplantation.

Left atrial structure and function and clinical outcomes in the general population.

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(0.67) (mass/EDV(0.67))] and function (ejection fraction) were assessed using linear regression analysis. The incremental prognostic value of LAmax/BSA and LAEF beyond traditional risk factors, LV ejection fraction, and LV mass was assessed using the Cox proportional-hazards model. Both increasing LAmax/BSA and decreasing LAEF were associated with hypertension and natriuretic peptide levels (P < 0.05 for all). In multivariable analysis, LAmax/BSA was most strongly associated with LV end-diastolic volume/BSA, while LAEF was strongly associated with LV ejection fraction and concentricity(0.67). During a median follow-up period of 8.1 years, there were 81 total deaths. Decreasing LAEF [hazard ratio (HR) per 1 standard deviation (SD) (8.0%): 1.56 (1.32-1.87)] but not increasing LAmax/BSA [HR per 1 SD (8.6 mL/m(2)): 1.14 (0.97-1.34)] was independently associated with mortality. Furthermore, the addition of LAEF to a model adjusting Framingham risk score, diabetes, race, LV mass, and ejection fraction improved the c-statistic (c-statistics: 0.78 vs. 0.77; P < 0.05, respectively), whereas the addition of LAmax/BSA did not (c-statistics: 0.76, P = 0.20). CONCLUSION: In the general population, both LAmax/BSA and LAEF are important subclinical phenotypes but LAEF is superior and incremental to LAmax/BSA.

Tolerability of sirolimus: a decade of experience at a single cardiac transplant center.

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. We retrospectively reviewed records of all adult cardiac transplant recipients living between September 1999 and February 2010 (n = 329) and identified 67 patients (20%) who received sirolimus. The indications for sirolimus were cardiac allograft vasculopathy (67%), renal dysfunction (25%), rejection (4%), and intolerability of tacrolimus (3%). One-third of patients discontinued sirolimus at a median (25th, 75th percentiles) of 0.9 (0.2, 1.6) yr of duration. Over 70% of subjects experienced an adverse event attributed to sirolimus. Adverse events were associated with higher average sirolimus levels (9.1 ng/mL vs. 7.1 ng/mL, p = 0.004). We conclude that sirolimus is frequently used in cardiac transplant recipients (20%) and commonly causes side effects, often necessitating discontinuation. Higher average sirolimus levels were associated with adverse events, suggesting that tolerability may improve if levels are maintained within the lower end of the current therapeutic range; however, the improvement in tolerability would need to be balanced with the potential for decreased efficacy.

The natural history of new-onset heart failure with a severely depressed left ventricular ejection fraction: implications for timing of implantable cardioverter-defibrillator implantation.

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). The ICD implantation was delayed with plans to reassess LVEF approximately 6 months after optimization of ß-blockers. Mortality was ascertained by the National Death Index. RESULTS: Follow-up echocardiograms were performed in 115 of the 224 subjects. Of these, 50 (43%) had mildly depressed or normal LVEF at follow-up ("LVEF recovery") such that an ICD was no longer indicated. In a conservative sensitivity analysis (using the entire study cohort, whether or not a follow-up echocardiogram was obtained, as the denominator), 22% of subjects had LVEF recovery. Mortality at 6, 12, and 18 months in the entire cohort was 2.3%, 4.5%, and 6.8%, respectively. Of 87 patients who tolerated target doses of ß-blockers, only 1 (1.1%) died during the first 18 months. CONCLUSION: Patients with new-onset systolic HF have both a good chance of LVEF recovery and low 6-month mortality. Achievement of target ß-blocker dose identifies a very low-risk population. These data support delaying ICD implantation for a trial of medical therapy.

IIIB or not IIIB: a previously unanswered question.

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. Until the ambiguity is resolved, we suggest that this designation not be used in clinical practice or by investigators leading clinical trials assessing therapies which convey substantial risk to patients and therefore require clarity in describing the enrolled patient population. With ongoing improvements in LVADs, this therapy will increasingly be considered in patients less sick than those who require inotropic support, providing urgency to establish a consensus system of classifying such patients who nevertheless fall within the spectrum of advanced heart failure. Herein we propose a modification of the standard NYHA classification system which can be used to fill this void.

Left ventricular assist device support and myocardial recovery in recent onset cardiomyopathy.

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. The overall cohort (n = 373) was 38% female, 21% black, with a mean age of 45 ± 14 years. LVAD support was used in 3.8% (n = 14, 43% female, age 32 ± 10). Of LVAD subjects, 57% (8/14) were BTR, including 73% (8/11) of subjects with symptoms ≤4 months at the time of support. Left ventricular end-diastolic diameter (LVEDD) was smaller in BTR than nonrecovered (NR) subjects (P = .04). Myocardial inflammation was more common in BTR (75% versus 0%, P = .005), whereas fibrosis was less evident (25% versus 100%, P = .005). Of BTR subjects, 7/8 (87.5%) were alive and free of transplant with median follow-up of 19 months. CONCLUSION: In a multicenter registry of ROCM, BTR was common and occurred in the majority of subjects requiring LVAD support. Histology and LVEDD may assist in predicting potential for BTR in ROCM.

Implantable cardiac defibrillators and sudden death in recent onset nonischemic cardiomyopathy: results from IMAC2.

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) ≤0.40 and ≤6 months of symptoms. The mean age was 45 ± 14 years, 38% were female, 21% black, 75% New York Heart Association II/III, and the mean LVEF was 0.24 ± 0.08. Survival was comparable for subjects with an ICD within 1 month of entry (n = 43, 1/2/3 year % survival = 97/97/92) and those with no ICD at 1 month (n = 330, % survival = 98/97/95, P = .30) and between those with and without an ICD at 6 months (ICD, n = 73, 1/2/3 year % survival = 98/98/95; no ICD, n = 300, % survival = 98/96/95, P = .95). There were only 6 sudden cardiac deaths (SCD) noted (% survival free from SCD = 99/98/97) and these occurred in 1.9% of subjects without ICD and 0.9% of those with a device (P = .50). CONCLUSIONS: In a multicenter cohort of ROCM the risk of SCD was low at 1% per year. Early ICD placement did not impact survival and can be deferred while assessing potential for myocardial recovery.

Sirolimus use and incidence of venous thromboembolism in cardiac transplant recipients.

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. Rates of VTE were compared. Multivariable Cox proportional hazards models tested the association of sirolimus use with VTE. A higher incidence of VTE was seen in patients treated with vs. without sirolimus (8/67 [12%] vs. 9/134 [7%], log-rank statistic: 4.66, p=0.03). Lower body mass index (BMI) and total cholesterol levels were also associated with VTE (p<0.05). The association of sirolimus with VTE persisted when adjusting for BMI (hazard ratio [95% confidence interval]: 2.96 [1.13, 7.75], p=0.03) but not when adjusting for total cholesterol (p=0.08). These data suggest that sirolimus is associated with an increased risk of VTE in cardiac transplant recipients, a risk possibly mediated through comorbid conditions. Larger, more conclusive studies are needed. Until such studies are completed, a heightened level of awareness for VTE in cardiac transplant recipients treated with sirolimus appears warranted.

Risk scores versus natriuretic peptides for identifying prevalent stage B heart failure.

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). Stage B HF (n = 284) was defined by left ventricular (LV) hypertrophy, reduced LV ejection fraction, or prior myocardial infarction. We compared the utility of 2 risk scores (Health Aging and Body Composition HF risk score and the Framingham Heart Failure risk score) with B-type natriuretic peptide (BNP) and N-terminal pro-BNP in identifying stage B HF using logistic regression. RESULTS: Depending upon the method of indexing LV mass (body surface area, fat-free mass, or height(2.7)), the c-statistic for the Health Aging and Body Composition HF risk score (0.73, 0.75, and 0.64, respectively) was greater than that for BNP (0.62, 0.70, and 0.57, respectively) and N-terminal pro-BNP (0.62, 0.69, and 0.56, respectively) (P < .01 for all). These findings were similar for the Framingham Heart Failure risk score except when LV mass was indexed to fat-free mass. Addition of natriuretic peptide levels to the risk scores resulted in a modest but significant improvement in discrimination of stage B HF (Δ c-statistic, 0.01-0.03, P < .05 for all). CONCLUSIONS: Screening for stage B HF in the population is enhanced when natriuretic peptides are measured in addition to, rather than in place of, traditional risk scores.

Association of Health Aging and Body Composition (ABC) Heart Failure score with cardiac structural and functional abnormalities in young individuals.

BACKGROUND: The Health ABC Heart Failure score has recently been shown to predict 5-year risk of incident heart failure in the elderly. We tested whether this risk score is associated with subclinical phenotypes of heart failure in a younger population. METHODS: We stratified participants in the Dallas Heart Study aged 30 to 65 years who had a cardiac magnetic resonance imaging and no self-reported history of heart failure or cardiomyopathy into 4 previously defined Health ABC Heart Failure risk groups: low (<5%), average (5%-10%), high (10%-20%), and very high (>20% risk for heart failure within 5 years). We compared left ventricular (LV) structural and functional parameters and levels of B-type natriuretic peptide (BNP) and N-terminal proBNP among the 4 groups. RESULTS: In the study cohort (N = 2,540), the percentage of subjects in the low-, average-, high-, and very high risk groups was 78%, 15%, 6%, and 1%, respectively. Indexed LV mass (80 +/- 15 vs 90 +/- 20 vs 95 +/- 25 vs 116 +/- 41 g/m(2)), concentricity (1.6 +/- 0.3 vs 1.8 +/- 0.4 vs 2.0 +/- 0.5 vs 2.2 +/- 0.7 g/mL), median BNP (2.8 vs 3.7 vs 4.9 vs 7.5 pg/mL) and N-terminal proBNP (26 vs 30 vs 40 vs 58 pg/mL), and prevalent LV systolic dysfunction and LV hypertrophy progressively increased across risk groups (P < .001 for all) independent of gender or method of indexing LV mass. CONCLUSIONS: The Health ABC Heart Failure score was associated with subclinical cardiac structural changes in the general population 30 to 65 years of age, suggesting that it may be a valid tool for identification of young individuals at increased risk for heart failure.

Discussing Out-of-Pocket Costs With Patients: Shared Decision Making for Sacubitril-Valsartan in Heart Failure.

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. Methods and Results Structured interviews were conducted with 49 patients with heart failure with reduced ejection fraction at heart failure clinics and inpatient services. Patient opinions of the drug and its value were solicited after description of benefits using graphical displays. Descriptive quantitative analysis of closed-ended responses was conducted, and qualitative descriptive analysis of text data was performed. Of participants, 92% (45/49) said that they would definitely or probably switch to sacubitril-valsartan if their physician recommended it and out-of-pocket cost was $5 more per month than their current medication. Only 43% (21/49) would do so if out-of-pocket cost was $100 more per month ( P<0.001). At least 40% across all income categories would be unlikely to take sacubitril-valsartan at $100 more per month. Participants exhibited heterogeneous approaches to cost in decision making and varied on their use and interpretation of probabilistic information. Few (20%) participants stated physicians had initiated a conversation about cost in the past year. Conclusions Out-of-pocket cost variation reflective of contemporary cost sharing substantially influenced stated willingness to take sacubitril-valsartan, a guideline-recommended therapy with mortality benefit. These findings suggest a need for cost transparency to promote shared decision making. They also demonstrate the complexity of cost discussion and need to study how to incorporate out-of-pocket cost into clinical decisions.

Blacks and whites have a similar prevalence of reduced left ventricular ejection fraction in the general population: the Dallas Heart Study (DHS).

BACKGROUND: The objective of the study was to evaluate racial differences in the prevalence of left ventricular (LV) dysfunction. Few data compare the relative frequency of reduced LV ejection fraction (EF) (LVEF) in blacks and whites. Because of the higher prevalence of risk factors for heart failure in blacks, including hypertension, obesity, and LV hypertrophy, we hypothesized that LV dysfunction would also be more common in this ethnic group. METHODS: In the DHS, a probability-based sample of Dallas County, we performed cardiac magnetic resonance imaging on 1335 black and 858 white participants aged 30 to 67 years to measure LVEF and volumes. We compared the prevalence of reduced LV EF and distribution of ventricular volumes in the 2 ethnic groups. RESULTS: The prevalence of a reduced LVEF, whether defined as < 50%, < 55%, or < 60%, did not appear to be different between black versus white women (P > or = .7 for each) or men (P > or = .4 for each). Similar findings were seen using a recently defined sex-specific threshold (men < 55% and women < 61%) for low EF (P = .1). Mean LV end-diastolic and end-systolic volumes indexed to body surface area were also comparable in black and white men (P > or = .3) and women (P > or = .1). CONCLUSIONS: Despite having a higher prevalence of risk factors for heart failure, blacks as compared with whites did not have a higher prevalence of reduced LVEF in the general population.

HVAD: The ENDURANCE Supplemental Trial.

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. Post hoc analyses demonstrated increased mean arterial blood pressure as a significant independent risk factor for stroke. METHODS: The ENDURANCE Supplemental Trial was a prospective, multicenter evaluation of 465 patients with advanced heart failure ineligible for transplantation, randomized 2:1 to HVAD (n = 308) or control (n = 157). The primary endpoint was the 12-month incidence of transient ischemic attack or stroke with residual deficit 24 weeks post-event. Secondary endpoints included the composite of freedom from death, disabling stroke, and need for device replacement or urgent transplantation, as well as comparisons of stroke or transient ischemic attack rates in HVAD cohorts in ENDURANCE Supplemental and ENDURANCE. RESULTS: The enhanced blood pressure protocol significantly reduced mean arterial blood pressure. The primary endpoint was not achieved (14.7% with HVAD vs. 12.1% with control, noninferiority [margin 6%] p = 0.14). However, the secondary composite endpoint demonstrated superiority of HVAD (76.1%) versus control (66.9%) (p = 0.04). The incidence of stroke in HVAD subjects was reduced 24.2% in ENDURANCE Supplemental compared with ENDURANCE (p = 0.10), and hemorrhagic cerebrovascular accident was reduced by 50.5% (p = 0.02). CONCLUSIONS: The ENDURANCE Supplemental Trial failed to demonstrate noninferiority of HVAD versus control regarding the pre-specified primary endpoint. However, the trial confirmed that BP management is associated with reduced stroke rates in HVAD subjects. HVAD subjects, relative to control subjects, more commonly achieved the composite endpoint (freedom from death, disabling stroke, and device replacement or urgent transplantation). (A Clinical Trial to Evaluate the HeartWare™ Ventricular Assist System [ENDURANCE SUPPLEMENTAL TRIAL] [DT2]; NCT01966458).

Progression to Stage D Heart Failure Among Outpatients With Stage C Heart Failure and Reduced Ejection Fraction.

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%. RESULTS: The mean age of patients was 62 ± 15 years; 35% were women; 47% were white; 46% were black, and 7% were of other races; median baseline ejection fraction was 28% (25th to 75th percentile: 20% to 35%); and 47% had ischemic heart disease. After 3.0 years (25th to 75th percentile: 1.7 to 3.2 years), 112 patients progressed to Stage D (3-year incidence: 12.2%; 95% confidence interval [CI]: 10.2% to 14.6%; annualized: 4.5%; 95% CI: 3.8% to 5.5%), and 116 patients died before progression (3-year competing mortality: 12.9%; annualized: 4.7%; 95% CI: 3.9% to 5.6%). By 3 years, 25.1% of patients (95% CI: 22.2% to 28.1%) had either progressed to Stage D or died (annualized: 9.2%; 95% CI: 8.1% to 10.5%). Annualized progression rates were higher in black versus white patients (6.3% vs. 2.7%, respectively; p < 0.001), nonischemic versus ischemic patients (6.1% vs. 2.9%, respectively; p < 0.001), and in New York Heart Association functional class III to IV versus I to II patients (7.5% vs. 1.9%, respectively; p < 0.001) but were similar for men and women (4.7% vs. 4.2%, respectively; p = 0.53). Lower ejection fraction and blood pressure, renal and hepatic dysfunction, and chronic lung disease rates were additional predictors of progression. Predictors of competing mortality were different from those of disease progression. CONCLUSIONS: Among patients with Stage C HFrEF receiving care in a referral center, 4.5% progressed to Stage D HF each year, with earlier progression among black and nonischemic patients. These findings have implications for healthcare planning and resource allocation for these patients.

Discoveries in peripartum cardiomyopathy.

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. Numerous studies have demonstrated that when the diagnosis of PPCM is made with LVEF > 0.30, the probability is that recovery to LVEF ≥ 0.50 will occur in the overwhelming majority of subjects. PPCM patients diagnosed with severely depressed systolic function (LVEF < 0.30) and a remodeled left ventricle with greater dilatation (LVEDd ≥ 60mm) are least likely to reach the outcome recovery goals. These are the patients with the greatest need for newer interventional strategies.

Validation of clinical scores for right ventricular failure prediction after implantation of continuous-flow left ventricular assist devices.

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; 41.4% white and 56.0% black; 66.4% men; 56.0% bridge to transplant, 37.1% destination therapy, 17.4% bridge to decision) who received a continuous-flow LVAD (HeartMate II: 79 patients, HeartWare: 37 patients) between 2008 and 2013. RESULTS: Overall, 37 patients (31.9%) developed RVF, defined: as pulmonary vasodilator use for ≥48 hours or inotrope use for ≥14 days post-operatively; re-institution of inotropes; multi-organ failure due to RVF; or need for mechanical RV support. Median (Quartile 1 to Quartile 3) time to initial discontinuation of inotropes was 6 (range 4 to 8) days. Among scores, the Michigan score reached significance for RVF prediction but discrimination was modest (C = 0.62 [95% CI 0.52 to 0.72], p = 0.021; positive predictive value [PPV] 60.0%; negative predictive value [NPV] 75.8%), followed by CRITT (C = 0.60 [95% CI 0.50 to 0.71], p = 0.059; PPV 40.5%; NPV 72.2%). Other models did not significantly discriminate RVF. The newer, INTERMACS 3.0 definition for RVF, which includes inotropic support beyond 7 days, was reached by 57 patients (49.1%). The Kormos model performed best with this definition (C = 0.62 [95% CI 0.54 to 0.71], p = 0.005; PPV 64.3%; NPV 59.5%), followed by Penn (C = 0.61), Michigan (C = 0.60) and CRITT (C = 0.60), but overall score performance was modest. CONCLUSION: Current schemes for post-LVAD RVF risk prediction perform only modestly when applied to external populations.

Clinical Outcomes for Peripartum Cardiomyopathy in North America: Results of the IPAC Study (Investigations of Pregnancy-Associated Cardiomyopathy).

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. The LVEF was assessed by echocardiography at baseline and at 2, 6, and 12 months post-partum. Survival free from major cardiovascular events (death, transplantation, or left ventricular [LV] assist device) was determined. Predictors of outcome, particularly race, parameters of LV dysfunction (LVEF), and remodeling (left ventricular end-diastolic diameter [LVEDD]) at presentation, were assessed by univariate and multivariate analyses. RESULTS: The cohort was 30% black, 65% white, 5% other; the mean patient age was 30 ± 6 years; and 88% were receiving beta-blockers and 81% angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. The LVEF at study entry was 0.35 ± 0.10, 0.51 ± 0.11 at 6 months, and 0.53 ± 0.10 at 12 months. By 1 year, 13% had experienced major events or had persistent severe cardiomyopathy with an LVEF <0.35, and 72% achieved an LVEF ≥0.50. An initial LVEF <0.30 (p = 0.001), an LVEDD ≥6.0 cm (p < 0.001), black race (p = 0.001), and presentation after 6 weeks post-partum (p = 0.02) were associated with a lower LVEF at 12 months. No subjects with both a baseline LVEF <0.30 and an LVEDD ≥6.0 cm recovered by 1 year post-partum, whereas 91% with both a baseline LVEF ≥0.30 and an LVEDD <6.0 cm recovered (p < 0.00001). CONCLUSIONS: In a prospective cohort with PPCM, most women recovered; however, 13% had major events or persistent severe cardiomyopathy. Black women had more LV dysfunction at presentation and at 6 and 12 months post-partum. Severe LV dysfunction and greater remodeling at study entry were associated with less recovery. (Investigations of Pregnancy Associated Cardiomyopathy [IPAC]; NCT01085955).

Effect of pulsatile and nonpulsatile flow on cerebral perfusion in patients with left ventricular assist devices.

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. METHODS: Dynamic cerebral autoregulation was assessed in both time-domain (autoregulatory index) and frequency-domain (transfer function analysis) analyses in 9 CF-LVAD subjects, 5 pulsatile LVAD subjects and 10 healthy controls, by evaluating mean arterial pressure (MAP) and cerebral blood flow velocity (CBFV) during a sit-stand maneuver at 0.05 Hz (10-second sit, 10-second stand). The autoregulatory index was calculated as the percent change in mean CBFV per mm Hg change in MAP. RESULTS: The magnitude of oscillation in MAP and CBFV was greater in subjects with pulsatile LVADs than either CF-LVADs or healthy controls (p = 0.065 for MAP, p = 0.004 for CBFV). The autoregulatory index and transfer function gain were similar among groups, indicating that dynamic cerebral autoregulation is preserved among patients with CF-LVADs. CONCLUSIONS: Cerebral blood flow in patients with CF-LVADs is comparable to that of healthy controls across a range of blood pressures. Patients with pulsatile devices have greater oscillations in MAP and CBFV. However, dynamic cerebral autoregulation is preserved among subjects with either type of device. Thus, the reduction in pulsatility afforded by CF-LVADs does not impair normal autoregulatory processes.

High-sensitivity cardiac troponin I assay to screen for acute rejection in patients with heart transplant.

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. AR was defined as International Society for Heart and Lung Transplantation grade 2R or higher cellular rejection, acellular rejection, or allograft dysfunction of uncertain pathogenesis, leading to treatment for presumed rejection. cTnI was measured with a high-sensitivity assay (Abbott Diagnostics, Abbott Park, IL). Cross-sectional analyses determined the association of cTnI concentrations with rejection and International Society for Heart and Lung Transplantation grade and the performance metrics of cTnI for the detection of AR. Among 98 subjects, 37% had ≥1 rejection episode. cTnI was measured in 418 serum samples, including 35 paired to a rejection episode. cTnI concentrations were significantly higher in rejection versus nonrejection samples (median, 57.1 versus 10.2 ng/L; P<0.0001) and increased in a graded manner with higher biopsy scores (P(trend)<0.0001). The c-statistic to discriminate AR was 0.82 (95% confidence interval, 0.76-0.88). Using a cut point of 15 ng/L, sensitivity was 94%, specificity 60%, positive predictive value 18%, and negative predictive value 99%. CONCLUSIONS: A high-sensitivity cTnI assay seems useful to rule out AR in cardiac transplant recipients. If validated in prospective studies, a strategy of serial monitoring with a high-sensitivity cTnI assay may offer a low-cost noninvasive strategy for rejection surveillance.