Association of socioeconomic status in the incidence, quality-of-care metrics, and outcomes for patients with cardiogenic shock in a pre-hospital setting.

AIMS: The relationship between lower socioeconomic status (SES) and poor cardiovascular outcomes is well described; however, there exists a paucity of data exploring this association in cardiogenic shock (CS). This study aimed to investigate whether any disparities exist between SES and the incidence, quality of care or outcomes of CS patients attended by emergency medical services (EMS). METHODS AND RESULTS: This population-based cohort study included consecutive patients transported by EMS with CS between 1 January 2015 and 30 June 2019 in Victoria, Australia. Data were collected from individually linked ambulance, hospital, and mortality datasets. Patients were stratified into SES quintiles using national census data produced by the Australian Bureau of Statistics.A total of 2628 patients were attended by EMS for CS. The age-standardized incidence of CS amongst all patients was 11.8 [95% confidence interval (95% CI), 11.4-12.3] per 100 000 person-years, with a stepwise increase from the highest to lowest SES quintile (lowest quintile 17.0 vs. highest quintile 9.7 per 100 000 person-years, P-trend < 0.001). Patients in lower SES quintiles were less likely to attend metropolitan hospitals and more likely to be received by inner regional and remote centres without revascularization capabilities. A greater proportion of the lower SES groups presented with CS due to non-ST elevation myocardial infarction (NSTEMI) or unstable angina pectoris (UAP), and overall were less likely to undergo coronary angiography. Multivariable analysis demonstrated an increased 30-day all-cause mortality rate in the lowest three SES quintiles when compared with the highest quintile. CONCLUSION: This population-based study demonstrated discrepancies between SES status in the incidence, care metrics, and mortality rates of patients presenting to EMS with CS. These findings outline the challenges in equitable healthcare delivery within this cohort.

Cost-Effectiveness of Empagliflozin in Patients With Heart Failure and Preserved Ejection Fraction.

BACKGROUND: Empagliflozin is the first medication to demonstrate clinical benefit in patients with heart failure with preserved ejection fraction, but its cost-effectiveness is unknown. We aimed to evaluate the cost-effectiveness of adding empagliflozin to standard therapy in patients with heart failure with preserved ejection fraction. METHODS: A Markov model from the perspective of the Australian health care system was constructed to compare empagliflozin plus standard care to standard care alone among a hypothetical cohort of patients with heart failure with preserved ejection fraction. Clinical probabilities were derived from The EMPEROR-Preserved (Empagliflozin Outcome Trial in Patients with Chronic Heart Failure with Preserved Ejection Fraction). Costs and utilities were derived from published sources. The main outcome was the incremental cost-effectiveness ratio per quality-adjusted life-year gained. Deterministic and probabilistic sensitivity analyses were performed to assess model uncertainty. Costs and benefits were discounted at 5% annually. RESULTS: Over a lifetime, the addition of empagliflozin to standard care prevented 167 heart failure hospitalizations and 155 heart failure-related urgent care visits for every 1000 patients treated and increased mean quality-adjusted survival by 0.16 quality adjusted life-years per patient. Mean lifetime costs in the empagliflozin and standard care groups were AUD$63 218 and AUD$58 478 per patient, respectively. This resulted in an incremental cost-effectiveness ratio of AUD$29 202 per quality adjusted life-year gained. In probabilistic sensitivity analyses, empagliflozin was cost-effective in 85% of 10 000 Monte Carlo simulations at a willingness-to-pay threshold of AUD$50 000 per quality adjusted life-year gained. CONCLUSIONS: In patients with heart failure with preserved ejection fraction, adding empagliflozin to standard care is likely to be cost-effective when compared with standard care alone in the Australian health care setting.

Assessment of Predictors of Left Atrial Volume Response to a Transcatheter InterAtrial Shunt Device (from the REDUCE LAP-HF Trial).

In patients with heart failure and preserved or mildly reduced ejection fractions (EF ≥40%), implantation of an interatrial shunt device (IASD) resulted in heterogenous changes of the left atrial (LA) volume. Baseline characteristics that correlate with a favorable decrease in LA volume are unknown. We hypothesized that a larger ratio of left to right atrial volume at baseline would correlate strongly with LA volume decongestion following IASD implantation. Reduce Elevated LA Pressure in Patients With Heart Failure was a multicenter study of the safety and feasibility of IASD implantation. Sixty-four patients with EF ≥40% underwent device implantation along with baseline conventional echocardiograms, speckle tracking echocardiography, and resting and exercise hemodynamics. Higher LA compliance (-4.2%, p = 0.048) and right atrial reservoir strain (-0.8%, p = 0.005) were independently associated with a percent decrease in the systolic LA volume index from baseline to 6-months. In conclusion, greater LA volume reduction following IASD implantation is associated with higher baseline compliance of the left atrium and higher reservoir strain of the right atrium.

Accuracy of Echocardiographic Cardiac Index Assessment in Subjects with Preserved Left Ventricular Ejection Fraction.

INTRODUCTION: We aimed to determine the accuracy of the echocardiographic assessment of cardiac index (CI) in subjects with preserved left ventricular ejection fraction (LVEF). METHODS: Thirty-three subjects with LVEF >50%, normal sinus rhythm, and a broad spectrum of hemodynamic profiles underwent echocardiography immediately followed by right heart catheterization. As gold standards, CI was assessed using thermodilution [CI (TD)] and the Fick method [CI (F)]. Echocardiographic CI was assessed by four methods: from the left ventricular outflow tract (LVOT) velocity time integral and the LVOT diameter as measured [CI (LVOTm)] as well as estimated from body surface area [CI (LVOTe)], and from stroke volume indices assessed using the biplane [CI (BP)] and monoplane [CI (MP)] methods. RESULTS: The mean CI (TD), CI (F), CI (LVOTm), CI (LVOTe), CI (BP), and CI (MP) were 3.0 ± 0.9, 3.1 ± 0.7, 2.8 ± 0.6, 3.3 ± 0.6, 2.0 ± 0.6, and 2.2 ± 0.7 L/min/m(2) . There were modest correlations between CI (TD) and CI (F) and all four noninvasive measures of CI with r(2) values ranging from 0.09 to 0.30. CI (LVOTm) underestimated CI (TD) and CI (F) by 0.3 and 0.3 L/min/m(2) , CI (LVOTe) overestimated CI (TD) and CI (F) by 0.3 and 0.2 L/min/m(2) , and CI (BP) and CI (MP) underestimated CI (TD) and CI (F) by 1.1 and 1.1 L/min/m(2) and 0.9 and 0.9 L/min/m(2) , respectively, with large limits of agreement for all comparisons. CONCLUSIONS: In subjects with nondilated left ventricles with preserved LVEF, flow- or volume-based measures of CI by 2D echocardiography may not accurately reflect CI (TD) and CI (F). Further larger studies are required to verify our findings and to evaluate the accuracy of contrast and 3D echocardiography in this setting.

Noninvasive assessment of pulmonary vascular resistance by Doppler echocardiography.

BACKGROUND: The ratio of tricuspid regurgitation velocity (TRV) to the time-velocity integral of the right ventricular outflow tract (TVIRVOT) has been studied as a reliable measure to distinguish elevated from normal pulmonary vascular resistance (PVR). The equation TRV/TVIRVOT × 10 + 0.16 (PVRecho) has been shown to provide a good noninvasive estimate of PVR. However, its role in patients with significantly elevated PVR (> 6 Wood units [WU]) has not been conclusively evaluated. The aim of this study was to establish the validity of the TRV/TVIRVOT ratio as a correlate of PVR. The role of TRV/TVIRVOT was also compared with that of a new ratio, TRV(2)/TVIRVOT, in patients with markedly elevated PVR (>6 WU). METHODS: Data from five validation studies using TRV/TVIRVOT as an estimate of PVR were compared with invasive PVR measurements (PVRcath). Multiple linear regression analyses were generated between PVRcath and both TRV/TVIRVOT and TRV(2)/TVIRVOT. Both PVRecho and a new derived regression equation based on TRV(2)/TVIRVOT: 5.19 × TRV(2)/TVIRVOT - 0.4 (PVRecho2) were compared with PVRcath using Bland-Altman analysis. Logistic models were generated, and cutoff values for both TRV/TVIRVOT and TRV(2)/TVIRVOT were obtained to predict PVR > 6 WU. RESULTS: One hundred fifty patients remained in the final analysis. Linear regression analysis between PVRcath and TRV/TVIRVOT revealed a good correlation (r = 0.76, P < .0001, Z = 0.92). There was a better correlation between PVRcath and TRV(2)/TVIRVOT (r = 0.79, P < .0001, Z = -0.01) in the entire cohort as well as in patients with PVR > 6 WU. Moreover, PVRecho2 compared better with PVRcath than PVRecho using Bland-Altman analysis in the entire cohort and in patients with PVR > 6 WU. TRV(2)/TVIRVOT and TRV/TVIRVOT both predicted PVR > 6 WU with good sensitivity and specificity. CONCLUSIONS: TRV/TVIRVOT is a reliable method to identify patients with elevated PVR. In patients with TRV/TVIRVOT > 0.275, PVR is likely > 6 WU, and PVRecho2 derived from TRV(2)/TVIRVOT provides an improved noninvasive estimate of PVR compared with PVRecho.