Pulmonary Artery Catheter Usage and Impact on Mortality in Patients With Cardiogenic Shock: Results From a Canadian Single-Centre Registry

BACKGROUND

Hemodynamic assessment for cardiogenic shock (CS) phenotyping in patients has led to renewed interest in the use of pulmonary artery catheters (PACs).

METHODS

We included patients admitted with CS from January 2014 to December 2020 and compared clinical outcomes among patients who received PACs and those who did not. The primary outcome was the rate of in-hospital mortality. Secondary outcomes included use of advanced heart failure therapies and coronary intensive care unit (CICU) and hospital lengths of stay.

RESULTS

A total of 1043 patients were analysed and 47% received PACs. Patients selected for PAC-guided management were younger and had lower left ventricular function. They also had higher use of vasopressor and inotropes, and 15.2% of them were already supported with temporary mechanical circulatory support (MCS). In-hospital mortality was lower in patients who received PACs (29.3% vs 36.2%; P = 0.02), mainly driven by a reduction in mortality among those in Society for Cardiovascular Angiography and Interventions (SCAI) stages D and E CS. Patients who received PACs were more likely to receive temporary MCS with Impella, durable ventricular assist devices (VADs), or orthotopic heart transplantation (OHT) (P < 0.001 for all analyses). CICU and hospital lengths of stay were longer in patients who used PACs.

CONCLUSIONS

Among patients with CS, the use of PACs was associated with lower in-hospital mortality, especially among those in SCAI stages D and E. Patients who received PACs were also more frequently rescued with temporary MCS or received advanced heart failure therapies, such as durable VADs or OHT.

The Effect of Using a Remote Patient Management Platform in Optimizing Guideline-Directed Medical Therapy in Heart Failure Patients: A Randomized Controlled Trial

BACKGROUND

Guideline-directed medical therapy (GDMT) remains underutilized in patients with heart failure with reduced ejection fraction, leading to morbidity and mortality.

OBJECTIVES

The Medly Titrate (Use of Telemonitoring to Facilitate Heart Failure Mediation Titration) study was an open-label, randomized controlled trial to determine whether remote medication titration for patients with heart failure with reduced ejection fraction was more effective than usual care (UC).

METHODS

In this study, 108 patients were randomized to remote GDMT titration through the Medly heart failure program (n = 56) vs UC (n = 52). The primary outcome was the proportion of patients completing GDMT titration at 6 months. Secondary outcomes included the number of clinic visits and time required to achieve titration, patient health outcomes, and health care utilization, including urgent clinic/emergency department visits and hospitalization.

RESULTS

At 6 months, GDMT titration was completed in 82.1% (95% CI: 71.2%-90.8%) of patients in the intervention arm vs 53.8% in UC (95% CI: 41.1%-67.7%; P = 0.001). Remote titration required fewer in-person (1.62 ± 1.09 vs 2.42 ± 1.65; P = 0.004) and virtual clinic visits (0.50 ± 1.08 vs 1.29 ± 1.86; P = 0.009) to complete titration. Median time to optimization was shorter with remote titration (3.42 months [Q1-Q3: 2.99-4.04 months] vs 5.47 months [Q1-Q3: 4.14-7.33 months]; P < 0.001). The number of urgent clinic/emergency department visits (incidence rate ratio of remote vs control groups: 0.90 [95% CI: 0.53-1.56]; P = 0.70) were similar between groups, with a reduction in all-cause hospitalization with remote titration (incidence rate ratio: 0.55 [95% CI: 0.31-0.97]; P = 0.042).

CONCLUSIONS

Remote titration of GDMT in heart failure with reduced ejection fraction was effective, safe, feasible, and increased the proportion of patients achieving target doses, in a shorter period of time with no excess adverse events compared with UC. (Use of Telemonitoring to Facilitate Heart Failure Mediation Titration [Medly Titrate]; NCT04205513).

Long-term reduced functional capacity and quality of life in hospitalized COVID-19 patients

Background

Persistent symptoms and exercise intolerance have been reported after COVID-19, even months after the acute disease. Although, the long-term impact on exercise capacity and health-related quality of life (HRQoL) is still unclear.

Research question

To assess the long-term functional capacity and HRQoL in patients hospitalized due to COVID-19.

Study design and methods

This is a prospective cohort study, conducted at two centers in Brazil, that included post-discharge COVID-19 patients and paired controls. The cohort was paired by age, sex, body mass index and comorbidities, using propensity score matching in a 1:3 ratio. Patients were eligible if signs or symptoms suggestive of COVID-19 and pulmonary involvement on chest computed tomography. All patients underwent cardiopulmonary exercise testing (CPET) and a HRQoL questionnaire (SF-36) 6 months after the COVID-19. The main outcome was the percentage of predicted peak oxygen consumption (ppVO2). Secondary outcomes included other CPET measures and HRQoL.

Results

The study sample comprised 47 post-discharge COVID-19 patients and 141 healthy controls. The mean age of COVID-19 patients was 54 ± 14 years, with 19 (40%) females, and a mean body mass index of 31 kg/m2 (SD, 6). The median follow-up was 7 months (IQR, 6.5-8.0) after hospital discharge. PpVO2 in COVID-19 patients was lower than in controls (83% vs. 95%, p = 0.002) with an effect size of 0.38 ([95%CI], 0.04-0.70). Mean peak VO2 (22 vs. 25 mL/kg/min, p = 0.04) and OUES (2,122 vs. 2,380, p = 0.027) were also reduced in the COVID-19 patients in comparison to controls. Dysfunctional breathing (DB) was present in 51%. HRQoL was significantly reduced in post COVID patients and positively correlated to peak exercise capacity.

Interpretation

Hospitalized COVID-19 patients presented, 7 months after discharge, with a reduction in functional capacity and HRQoL when compared to historical controls. HRQoL were reduced and correlated with the reduced peak VO2 in our population.

Value of Invasive Hemodynamic Assessments in Patients Supported by Continuous-Flow Left Ventricular Assist Devices

Left ventricular assist devices (LVADs) are increasingly used in patients with end-stage heart failure (HF). There is a significant risk of HF admissions and hemocompatibility-related adverse events that can be minimized by optimizing the LVAD support. Invasive hemodynamic assessment, which is currently underutilized, allows personalization of care for patients with LVAD, and may decrease the need for recurrent hospitalizations. It also aids in triaging patients with persistent low-flow alarms, evaluating reversal of pulmonary vasculature remodeling, and assessing right ventricular function. In addition, it can assist in determining the precipitant for residual HF symptoms and physical limitation during exercise and is the cornerstone of the assessment of myocardial recovery. This review provides a comprehensive approach to the use of invasive hemodynamic assessments in patients supported with LVADs.

Clinical Significance of Postoperative Atrial Fibrillation in Hypertrophic Cardiomyopathy Patients Undergoing Septal Myectomy

BACKGROUND

The optimal management of hypertrophic cardiomyopathy (HCM) patients with postoperative atrial fibrillation (POAF) after surgical myectomy remains unknown. We sought to investigate the association between POAF and atrial fibrillation (AF) or cardioembolic events during follow-up to bridge this gap.

METHODS

Patients undergoing surgical myectomy at 2 HCM referral centres in North America from 2002 to 2020 were included in this study. Patients with preoperative AF were excluded. POAF was defined as any episode of AF within 30 days after surgery.

RESULTS

Of 1176 patients, 375 (31.9%) had POAF. Age (adjusted hazard ratio [HR] 1.05, 95% confidence interval [CI] 1.03-1.06; P < 0.001), premyectomy left atrial diameter (LAD; adjusted HR 1.6, 95% CI 1.32-2.02; P < 0.001), and smoking (adjusted HR 1.60, 95% CI 1.17-2.20; P = 0.001) were associated with POAF on multivariable analysis. Of 934 patients with follow-up data, of duration 4.3 ± 4.1 years, AF was detected in 86 (9.2%). Only POAF (HR 4.20, 95% CI 2.44-7.23; P < 0.001), previous history of stroke (HR 4.81, 95% CI 1.63-14.17; P = 0.01), and postmyectomy LAD (HR 1.80, 95% CI 1.21-2.70; P = 0.004) were associated with AF incidence during follow-up. Cardioembolic events occurred in only 15 patients (1.6%). POAF was not associated with increased cardioembolic risk, with only 3 patients with POAF suffering such an event, all more than 4 years after surgery.

CONCLUSIONS

POAF is common in HCM patients undergoing myectomy and is a predictor of AF during follow-up. Over long-term follow-up, cardioembolic events are uncommon. These findings suggest that routine long-term anticoagulation for all HCM patients with postmyectomy AF is not justified after the initial postoperative period.

Association of duration and intensity of exercise with phenotypic expression in hypertrophic cardiomyopathy

OBJECTIVES

There is limited data regarding the impact of exercise on phenotypic expression in hypertrophic cardiomyopathy (HCM). We aimed to investigate whether such an association exists in a cohort of genotype-positive HCM patients.

METHODS

In this cross-sectional study of genotype-positive HCM families, we used structured questionnaires to obtain data regarding intensity and duration of exercise of participants starting at the age of 10, as well as data regarding exercise recommendations and their impact on quality of life (QOL). The association of cumulative metabolic-equivalent hours of exercise at different ages with different measures of phenotypic expression (maximal wall thickness, left atrial diameter, extent of late gadolinium enhancement) was analyzed.

RESULTS

The study included 109 patients from 55 families, including 43 male (39%) and 90 (83%) phenotype-positive. No association was identified between exercise duration or intensity with any of the phenotypic markers with the exception of greater cumulative exercise associated with younger age at presentation. Similar results were obtained when analysis was limited to exercise until the age of 20, until the age of 30 or only after 30. Among phenotype-positive patients, 89% recalled receiving recommendations regarding exercise restriction, 29% noted reduction in exercise level following such recommendations and 25% noted this having a significant impact on their QOL.

CONCLUSION

We found no association between exercise intensity or duration and phenotypic expression in genotype-positive HCM patients. These findings are important for physician-patient discussions and support the recent trend towards more permissive exercise restrictions in HCM.

Acute complication posttransplant: primary allograft dysfunction

PURPOSE OF REVIEW

Heart transplant is the gold standard treatment for patients with end-stage heart failure, improving both quality of life and survival. Despite advances in donor and recipient management, primary graft dysfunction (PGD) remains the most common cause of morbidity and mortality in the early posttransplant period. This review summarizes recent discoveries in the underlying pathophysiology, risk prediction and management of PGD.

RECENT FINDINGS

The incidence of PGD appears to be rising and it is not clear whether this is due to better recognition or secular changes in transplant practice. The utilization of donation after circulatory death organs for transplant is a further consideration for the development of PGD. Organ transport systems and preservation techniques may help to prevent PGD. As some of the risk factors for developing PGD remain modifiable, we summarize the current evidence for prevention and management of PGD.

SUMMARY

A better understanding will allow us to appropriately manage donors and recipients to reduce the complex interactions that lead to PGD. The development of an international consortium provides the opportunity for deep phenotyping and development of contemporary risk prediction models for PGD, which may reduce the incidence and consequent early mortality associated with heart transplantation.

Improved mortality and haemodynamics with milrinone in cardiogenic shock due to acute decompensated heart failure

AIMS

Studies in cardiogenic shock (CS) often have a heterogeneous population of patients, including those with acute myocardial infarction and acute decompensated heart failure (ADHF-CS). The therapeutic profile of milrinone may benefit patients with ADHF-CS. We compared the outcomes and haemodynamic trends in ADHF-CS receiving either milrinone or dobutamine.

METHODS AND RESULTS

Patients presenting with ADHF-CS (from 2014 to 2020) treated with a single inodilator (milrinone or dobutamine) were included in this study. Clinical characteristics, outcomes, and haemodynamic parameters were collected. The primary endpoint was 30 day mortality, with censoring at the time of transplant or left ventricular assist device implantation. A total of 573 patients were included, of which 366 (63.9%) received milrinone and 207 (36.1%) received dobutamine. Patients receiving milrinone were younger, had better kidney function, and lower lactate at admission. In addition, patients receiving milrinone received mechanical ventilation or vasopressors less frequently, whereas a pulmonary artery catheter was more frequently used. Milrinone use was associated with a lower adjusted risk of 30 day mortality (hazard ratio = 0.52, 95% confidence interval 0.35-0.77). After propensity-matching, the use of milrinone remained associated with a lower mortality (hazard ratio = 0.51, 95% confidence interval 0.27-0.96). These findings were associated with improved pulmonary artery compliance, stroke volume, and right ventricular stroke work index.

CONCLUSIONS

The use of milrinone compared with dobutamine in patients with ADHF-CS is associated with lower 30 day mortality and improved haemodynamics. These findings warrant further study in future randomized controlled trials.

Clonal hematopoiesis confers an increased mortality risk in orthotopic heart transplant recipients

Novel risk stratification and non-invasive surveillance methods are needed in orthotopic heart transplant (OHT) to reduce morbidity and mortality post-transplant. Clonal hematopoiesis (CH) refers to the acquisition of specific gene mutations in hematopoietic stem cells linked to enhanced inflammation and worse cardiovascular outcomes. The purpose of this study was to investigate the association between CH and OHT. Blood samples were collected from 127 OHT recipients. Error-corrected sequencing was used to detect CH-associated mutations. We evaluated the association between CH and acute cellular rejection, CMV infection, cardiac allograft vasculopathy (CAV), malignancies, and survival. CH mutations were detected in 26 (20.5%) patients, mostly in DNMT3A, ASXL1, and TET2. Patients with CH showed a higher frequency of CAV grade 2 or 3 (0% vs. 18%, p < .001). Moreover, a higher mortality rate was observed in patients with CH (11 [42%] vs. 15 [15%], p = .008) with an adjusted hazard ratio of 2.9 (95% CI, 1.4-6.3; p = .003). CH was not associated with acute cellular rejection, CMV infection or malignancies. The prevalence of CH in OHT recipients is higher than previously reported for the general population of the same age group, with an associated higher prevalence of CAV and mortality.

Prediction, prevention, and management of right ventricular failure after left ventricular assist device implantation: A comprehensive review

Left ventricular assist devices (LVADs) are increasingly common across the heart failure population. Right ventricular failure (RVF) is a feared complication that can occur in the early post-operative phase or during the outpatient follow-up. Multiple tools are available to the clinician to carefully estimate the individual risk of developing RVF after LVAD implantation. This review will provide a comprehensive overview of available tools for RVF prognostication, including patient-specific and right ventricle (RV)-specific echocardiographic and hemodynamic parameters, to provide guidance in patient selection during LVAD candidacy. We also offer a multidisciplinary approach to the management of early RVF, including indications and management of right ventricular assist devices in this setting to provide tools that help managing the failing RV.

Non-invasive assessment of right ventricular function and pulmonary pressures in cardiogenic shock remains challenging: don't pack away the PAC just yet

Background

Cardiogenic shock (CS) is associated with high levels of morbidity and mortality despite advances in treatment. Patients with right ventricle (RV) dysfunction have been shown to have poorer outcomes. It is suggested that invasive monitoring through pulmonary artery catheter (PAC) placement can assist in guiding management to improve survival, though they are associated with adverse events.

Purpose

This study assessed the utility of non-invasive, echocardiographic assessment of RV performance and pulmonary artery pressures (PAP) in patients with CS.

Methods

Consecutive patients admitted to a North American quaternary cardiac intensive care unit who had PAC placement were recruited into this study. Invasive haemodynamic assessment was followed by transthoracic echocardiography (TTE) performed by a critical care cardiologist, blinded to the invasive measurements. TTE images were later reported by a second cardiologist, blinded to the invasive measurements and the patient. Correlations between RV and pulmonary invasive and non-invasive parameters were evaluated using Pearson's correlation.

Results

Overall, 96 assessments of 60 patients were compared. Patients were predominantly male (73%), aged 58±14 years and SCAI stage C (55%) and D (22%) at the time of assessment. Invasive measurements of right heart and pulmonary function was possible in all patients. Mean RAP was 8.5±4.7 mmHg, systolic PAP 37.5±9.9 mmHg, diastolic PAP 18.1±6.5 mmHg, mean PAP 25.1±7.2 mmHg, pulmonary capillary wedge pressure (PCWP) 16.0±16.4 mmHg, pulmonary vascular resistance (PVR) 157±99dyn s cm–5, RV stroke work index (RVSWI) 7.0±3.9 g min/m2 and PAP index (PAPi) 2.9±4.2. When compared to non-invasive echocardiographic parameters, there was little correlation with invasive values (Table). RVSWI moderately correlated with peak tricuspid regurgitation (TR) velocity, tricuspid annular plane systolic excursion (TAPSE) and estimated systolic PAP; while peak TR velocity was mild-moderately correlated with PAP and PCWP. No single non-invasive parameter demonstrated strong prediction of invasive values.

Conclusion

Non-invasive assessment of right heart and pulmonary haemodynamic parameters is of limited validity when compared with invasive monitoring through PAC in patients with CS. PAC remains the most reliable method of assessing the RV haemodynamic profile in CS. Future studies should evaluate the clinical benefit of invasive haemodynamic monitoring in this population.

Funding Acknowledgement

Type of funding sources: None.

Echocardiographic assessment alone is inadequate for determining elevated left sided filling pressures in patients with cardiogenic shock

Background

Left atrial (LA) filling pressure assessment is of paramount importance in tailoring treatments for patients with cardiogenic shock (CS). ESC guidelines advocate for the use of mitral inflow Doppler and mitral annulus tissue Doppler measurements to predict elevated left atrial pressure in clinical practice. Echocardiographic measurement of LA pressures could reduce the need for invasive monitoring in CS patients, but its utility remains unproven in this population.

Purpose

We assessed the validity of mitral inflow velocity and mitral annulus velocity indices to determine LA pressures, correlating them with invasive measurement of pulmonary capillary wedge pressure (PCWP) in CS patients admitted to the cardiac intensive care unit (CICU).

Methods

We prospectively evaluated consecutive patients who underwent pulmonary artery catheter insertion in the CICU, measuring their haemodynamic parameters, including PCWP. This was immediately followed by a transthoracic echocardiography (TTE) performed by a critical care cardiologist, blinded to the invasive measurements. The early (E) and late (A) mitral inflow velocities were measured using mitral inflow Doppler and septal and lateral mitral annulus velocities (e') were measured using tissue Doppler, all in the apical 4-chamber view. TTE images were later reported by a second cardiologist, blinded to the invasive measurements and the patient. Correlations between E; E/A ratio; E/e' ratio and PCWP were evaluated using Pearson's correlation.

Results

Sixty patients were recruited into the study, aged 58±14 years, 27% female, with 96 assessments undertaken. The majority (55%) of patients were SCAI stage C, with 14% having had a cardiac arrest prior to CICU admission and 27% required mechanical ventilation at the time of assessment. Mean PCWP was 16.0±6.5 mmHg. Full mitral valve Doppler and tissue Doppler profiles were measured in 67 (70%) assessments, limited due to E/A fusion, atrial fibrillation and limited acoustic windows. There was only weak correlation between PCWP and E/A ratio (R=0.33, p=0.01), with no correlation between PCWP and the other measured values (Table 1), including E/e'. The AUC for identifying patients with elevated PCWP (≥15 mmHg) using E/A ratio was 0.67 (p=0.02), although there was no suitable value to use as a cut off with adequate sensitivity and specificity (Figure 1).

Conclusion

Echocardiographic non-invasive assessment of left sided cardiac filling pressures is technically challenging in patients with CS. Even when possible, there is weak correlation between echocardiographic and invasive measurements, suggesting limited value in this technique. Alternative non-invasive modalities, such as lung ultrasound, should be investigated in this population to assist clinical assessment.

Funding Acknowledgement

Type of funding sources: None.

Use of a remote telemonitoring platform significantly improves medication optimisation in heart failure patients

Background

Guideline directed medical therapy (GDMT) has been shown to reduce morbidity and mortality in patients with heart failure with reduced ejection fraction (HFrEF). Despite this, a large number of eligible patients do not receive these treatments or have prolonged delays in achieving optimal doses.

Purpose

To determine whether a telemonitoring-supported, remote medication optimisation programme could increase the proportion of HFrEF patients reaching maximum tolerated GDMT, in a shorter period of time compared to usual care.

Methods

A prospective, randomised controlled trial recruited 108 patients with a diagnosis of HFrEF from the ambulatory heart function clinic of a North American cardiac centre. All patients were enrolled onto a non-invasive remote monitoring platform which allowed daily nurse coordinator-led assessment of patient-reported symptoms and trends in heart rate, blood pressure and weight. In the remote titration intervention group, telemonitoring data were used by treating physicians to make decisions on optimisation of GDMT every two weeks, which was enacted by the patient's nurse coordinator, with no physician visit required. Patients in the control group were reviewed in clinic by their treating physician, where medication doses were optimised as per standard of care. The proportion of patients achieving maximum tolerated GDMT, and the time taken for this were compared between groups. Continuous data are presented as mean±standard deviation and compared with Student's t-test, while categorical data are shown as number (%) and compared using the Chi-squared test.

Results

108 patients (69.4% male, mean age 54.1±15.4 years) were recruited with a median follow-up of 740 days. Baseline characteristics and medication prescription were similar between groups (56 randomised to remote titration, RT, 52 to usual care, UC, see Table). There were three withdrawals from the RT group and two from the UC group. Significantly more patients in the RT group 52/53 (98.1%) achieved the primary outcome, reaching maximum tolerated GDMT, compared with 42/50 (84.0%) in the UC group (p=0.01). The RT group achieved GDMT earlier (123±70 vs. 183±136 days, p=0.01) with a 40% reduction in clinic visits (p&lt;0.01). In a time-to-event analysis, time to optimisation was significantly shorter in the intervention group (median 105 vs. 165 days, p[log rank] &lt;0.01, see Figure). There was a similar increase in prescription of GDMT in both groups and no differences in hospitalisation or urgent clinic review suggesting that there was no excess hazard of remote titration.

Conclusion

Remote titration of GDMT in HFrEF patients resulted in more patients achieving maximum tolerated doses, on average two months earlier, with a reduction in clinic visits and no excess adverse outcomes. Telemonitoring-supported remote GDMT titration is effective, safe and could reduce healthcare costs associated with the management of HFrEF.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): DHB is supported by a post-doctoral fellowship award from TRANSFORM-HF (Ontario, Canada).

Lung ultrasound predicts left-sided filling pressures in patients with cardiogenic shock admitted to the cardiac intensive care unit

Background

Left and right filling pressures, as well as cardiac output, are key targets in optimising treatment of cardiogenic shock (CS). Invasive pulmonary artery catheters can provide these data but are associated with complications and are not available in all hospital settings. Lung ultrasound (LUS) can detect pulmonary congestion in patients with heart failure (HF) and may be an alternative to invasive monitoring. We assessed the correlation between LUS score and invasive haemodynamic parameters in patients with CS admitted to the cardiac intensive care unit (CICU) of a North American cardiac centre.

Methods

We prospectively evaluated consecutive patients who underwent pulmonary artery catheter insertion in the CICU. Haemodynamic parameters including right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) were measured and cardiac output (CO) was calculated using the thermodilution method. This was immediately followed by an 8-zones LUS done by a critical care cardiologist who was blinded to the invasive hemodynamic measurements. The LUS score was calculated by counting the total number of B-lines in all 8 zones, with a higher score indicating greater congestion. Correlations between LUS score and hemodynamic parameters were evaluated using Pearson's correlation.

Results

Ninety-six measurements from 60 patients were included, aged 58±14 years with 27% female. The most common diagnosis at admission was cardiogenic shock, followed by acute myocardial infarction and HF exacerbation. Most patients were at SCAI stages C and D at the time of assessment. The mean number of B-lines at LUS was 10.1±8.2. Mean RAP was 8.5±4.6 mmHg, PCWP 16.2±6.3 mmHg and CO of 5.0±1.8 L/min. The total number of B-lines was correlated with PCWP (r=0.66, P&lt;0.001, see Figure 1), RAP (r=0.26, P&lt;0.001) and cardiac output (r=−0.23, p=0.02). Due to the correlation of B-lines in LUS with PCWP, we then evaluated the area under the ROC of the LUS to identify patients with PCWP ≥15 mmHg. The number of positive zones (≥3 B-lines) showed an AUC of 0.81 (0.72–0.89), P&lt;0.001. In 36 patients, we had repeated measurement with more than 12 hours apart. The delta change in PCWP was correlated with delta change in the number of B-lines (r=0.59, P&lt;0.001).

Conclusion

Elevated LUS score in patients with CS is associated with worse invasively-measured LV filling pressures, but less so with RAP or CO. LUS can serve as a useful adjunct to the clinical assessment of patients with CS who do not receive invasive hemodynamic monitoring, either at a single timepoint or to detect changes in clinical status over time, to guide ongoing management.

Funding Acknowledgement

Type of funding sources: None.

Patient Outcomes and Characteristics in a Contemporary Quaternary Canadian Cardiac Intensive Care Unit

Background

The modern-day cardiac intensive care unit (CICU) has evolved to care for patients with acute critical cardiac illness. We describe the current population of cardiac patients in a quaternary CICU.

Methods

Consecutive CICU patients admitted to the CICU at the Toronto General Hospital from 2014 to 2020 were studied. Patient demographics, admission diagnosis, critical care resources, complications, in-hospital mortality, and CICU and hospital length of stay were recorded.

Results

A total of 8865 consecutive admissions occurred, with a median age of 64.9 years. The most common primary cardiac diagnoses were acute decompensated heart failure (17.8%), non ST-elevation myocardial infarction (16.8%), ST-elevation myocardial infarction (15.5%), and arrhythmias (14.7%). Cardiogenic shock was seen in 13.2%, and out-of-hospital cardiac arrest in 4.1%. A noncardiovascular admission diagnosis accounted for 13.9% of the cases. Over the period studied, rates of admission were higher for cardiogenic shock (P < 0.001 for trend), with a higher use of critical care resources. Additionally, rates of admission were higher in female patients and those who had chronic kidney disease and diabetes. The in-hospital mortality rate of all CICU admissions was 13.2%, and it was highest in those with noncardiac conditions, compared to the rate in those with cardiac diagnoses (29.4% vs 10.6%, P < 0.001).

Conclusions

Given the trends of higher acuity of patients with cardiac critical illness, with higher use of critical care resources, education streams for critical care within cardiology, and alternative pathways of care for patients who have lower-acuity cardiac disease remain imperative to manage this evolving population.

Clonal haematopoiesis is associated with higher mortality in patients with cardiogenic shock

AIMS

Cardiogenic shock (CS) with variable systemic inflammation may be responsible for the patient heterogeneity and the exceedingly high mortality rate. Cardiovascular events have been associated with clonal haematopoiesis (CH) where specific gene mutations in hematopoietic stem cells lead to clonal expansion and the development of inflammation. This study aims to assess the prevalence of CH and its association with survival in a population of CS patients in a quaternary center.

METHODS

We compared the frequency of CH mutations among 341 CS patients and 345 ambulatory heart failure (HF) matched for age, sex, ejection fraction, and HF aetiology. The association of CH with survival and levels of circulating inflammatory cytokines was analysed.

RESULTS

We detected 266 CH mutations in 149 of 686 (22%) patients. CS patients had a higher prevalence of CH-related mutations than HF patients (OR 1.5; 95% CI 1.0-2.1, P=0.02) and was associated with decreased survival (30-days: HR 2.7; 95% CI 1.3-5.7, P=0.006; 90-days: HR 2.2; 95% CI 1.3-3.9, P=0.003; and 3-years: HR 1.7; 95% CI 1.1-2.8, P=0.01). TET2 or ASXL1 mutations were associated with lower survival in CS patients at all-time points (P≤0.03). CS patients with TET2 mutations had higher circulating levels of SCD40L, IFNγ, IL-4, and TNFα (P≤0.04), while those with ASXL1 mutations had decreased levels of CCL7 (P=0.03).

CONCLUSIONS

CS patients have high frequency of CH, notably mutations in TET2 and ASXL1. This was associated with reduced survival and dysregulation of circulating inflammatory cytokines in those CS patients with CH. This article is protected by copyright. All rights reserved.

CALL-K score: predicting the need for renal replacement therapy in cardiogenic shock

AIMS

The clinical predictors and outcomes of patients with cardiogenic shock (CS) requiring renal replacement therapy (RRT) have not been studied previously. This study assesses the impact of RRT on mortality in patients with CS and aims to identify clinical factors that contribute to the need of RRT.

METHODS AND RESULTS

Consecutive patients presenting with CS were included from a prospective registry of cardiac intensive care unit admissions at a single institution between 2014 and 2020. Of the 1030 patients admitted with CS, 123 (11.9%) received RRT. RRT was associated with higher 1-year mortality [adjusted hazard ratio = 1.62, 95% confidence interval (CI) 1.02-2.14], and a higher in-hospital incidence of sepsis [risk ratio = 2.76, P < 0.001], and pneumonia (risk ratio = 2.9, P = 0.001). Those who received RRT were less likely to receive guideline-directed medical treatment at time of discharge, undergo heart transplantation (2.4% vs. 11.5%, P = 0.002) or receive a durable left ventricular assist device (0.0% vs. 11.6%, P < 0.001). Five variables at admission best predicted the need for RRT (age, lactate, haemoglobin, use of pre-admission loop diuretics, and admission estimated glomerular filtration rate) and were used to generate the CALL-K 9-point risk score, with better discrimination than creatinine alone (P = 0.008). The score was internally validated (area under the curve = 0.815, 95% CI 0.739-0.835) with good calibration (Hosmer-Lemeshow P = 0.827).

CONCLUSIONS

RRT is associated with worse outcomes, including a lower likelihood to receive advanced heart failure therapies in patients with CS. A risk score comprising five variables routinely collected at admission can accurately estimate the risk of needing RRT.

Digital Technology Application for Improved Responses to Health Care Challenges: Lessons Learned From COVID-19

While COVID-19 is still ongoing and associated with more than 5 million deaths, the scope and speed of advances over the past year in terms of scientific discovery, data dissemination, and technology have been staggering. It is not a matter of “if” but “when” we will face the next pandemic, and how we leverage technology and data management effectively to create flexible ecosystems that facilitate collaboration, equitable care, and innovation will determine its severity and scale. The aim of this review is to address emerging challenges that came to light during the pandemic in health care and innovations that enabled us to adapt and continue to care for patients. The pandemic highlighted the need for seismic shifts in care paradigms and technology with considerations related to the digital divide and health literacy for digital health interventions to reach full potential and improve health outcomes. We discuss advances in telemedicine, remote patient monitoring, and emerging wearable technologies. Despite the promise of digital health, we emphasise the importance of addressing its limitations, including interpretation challenges, accuracy of findings, and artificial intelligence–driven algorithms. We summarise the most recent recommendation of the Virtual Care Task Force to scaling virtual medical services in Canada. Finally, we propose a model for optimal implementation of health digital innovations with 5 tenets including data management, data security, digital biomarkers, useful artificial intelligence, and clinical integration.

Prognostic Value of Peak Oxygen Uptake in Patients Supported With Left Ventricular Assist Devices (PRO-VAD)

OBJECTIVES

The purpose of this study was to examine whether peak oxygen uptake (pVO₂) and other cardiopulmonary exercise test (CPET)-derived variables could predict intermediate-term mortality in stable continuous flow LVAD recipients.

BACKGROUND

pVO₂ is a cornerstone in the selection of patients for heart transplantation, but the prognostic power of pVO₂ obtained in patients treated with a left ventricular assist device (LVAD) is unknown.

METHODS

We collected data for pVO₂ and outcomes in adult LVAD recipients in a retrospective, multicenter study and evaluated cutoff values for pVO₂ including: 1) values above or below medians; 2) grouping patients in tertiles; and 3) pVO₂ ≤14 ml/kg/min if the patient was not treated with beta-blockers (BB) or pVO₂ ≤12 ml/kg/min if the patient was taking BB therapy.

RESULTS

Nine centers contributed data from 450 patients. Patients were 53 ± 13 years of age; 78% were male; body mass index was 25 ± 5 kg/m² with few comorbidities (stroke: 11%; diabetes: 18%; and peripheral artery disease: 4%). The cause of heart failure (HF) was most often nonischemic (66%). Devices included were the HeartMate II and 3 (Abbott); and Heartware ventricular assist devices Jarvik and Duraheart (Medtronic). The index CPET was performed at a median of 189 days (154 days-225 days) after LVAD implantation, and mean pVO₂ was 14.1 ± 5 ml/kg/min (47% ± 14% of predicted value). Lower pVO₂ values were strongly associated with poorer survival regardless of whether patients were analyzed for absolute pVO₂ in ml/kg/min, pVO₂ ≤12 BB/14 ml/kg/min, or as a percentage of predicted pVO₂ values (P ≤ 0.001 for all). For patients with pVO₂ >12 BB/14 and ventilation/carbon dioxide relationship (VE/VCO₂) slope <35, the 1-year survival was 100%.

CONCLUSIONS

Even after LVAD implantation, pVO₂ has prognostic value, similar to HF patients not supported by mechanical circulatory support devices. (PROgnostic Value of Exercise Capacity Measured as Peak Oxygen Uptake [pVO₂] in Recipients of Left Ventricular Assist Devices [PRO-VAD]; NCT04423562).

Liberation From Venoarterial Extracorporeal Membrane Oxygenation: A Review

Venoarterial extracorporeal membrane oxygenation may be used for circulatory support in cardiogenic shock as a bridge to recovery, a bridge to a ventricular assist device (VAD), or a bridge to transplant. While the determination of potential exit strategies is essential before cannulation, the final determination of a patient's options may change, in part, through their in-hospital clinical course. We propose that liberation from venoarterial extracorporeal membrane oxygenation should be conceptualized as a process of discovery in the assessment of a patient's underlying clinical status and a key driver of further clinical decision-making. A trial of liberation from support should be considered when the goals of the weaning trial are well-defined and, ideally, in the absence of potentially confounding clinical factors. In this review, we will discuss readiness to wean criteria from venoarterial extracorporeal membrane oxygenation, as well as specific clinical, biochemical, and echocardiographic parameters that may prove useful in determining weaning timing and revealing the patient's underlying hemodynamic status and prognosis. The role of various cannula configurations, support devices, and pharmacological adjuncts will also be discussed. Finally, we highlight current gaps in evidence and suggest areas of future research.

The effect of antiplatelet therapy on survival and cardiac allograft vasculopathy following heart transplantation: A systematic review and meta-analysis

Cardiac allograft vasculopathy (CAV) is mediated by endothelial inflammation, platelet activation and thrombosis. Antiplatelet therapy may prevent the development of CAV. This systematic review and meta-analysis summarizes and appraises the evidence on the effect of antiplatelet therapy after heart transplantation (HT). CENTRAL(Ovid), MEDLINE(Ovid), Embase(Ovid) were searched from inception until April 30, 2020. Outcomes included CAV, all-cause mortality, and CAV-related mortality. Data were pooled using random-effects models. Seven observational studies including 2023 patients, mean age 52 years, 22% female, 47% with ischemic cardiomyopathy followed over a mean 7.1 years proved eligible. All studies compared acetylsalicylic acid (ASA) to no treatment and were at serious risk of bias. Data from 1911 patients in 6 studies were pooled in the meta-analyses. The evidence is very uncertain about the effect of ASA on all-cause or CAV-related mortality. ASA may reduce the development of CAV (RR 0.75, 95% CI: 0.44-1.29) based on very low certainty evidence. Two studies that conducted propensity-weighted analyses showed further reduction in CAV with ASA (HR 0.31, 95% CI: 0.13-0.74). In conclusion, there is limited evidence that ASA may reduce the development of CAV. Definitive resolution of the impact of antiplatelet therapy on CAV and mortality will require randomized clinical trials.

Impact of Remote Titration Combined With Telemonitoring on the Optimization of Guideline-Directed Medical Therapy for Patients With Heart Failure: Internal Pilot of a Randomized Controlled Trial

Background

To improve health outcomes in patients with heart failure, guideline-directed medical therapy (GDMT) should be optimized to target doses. However, GDMT remains underutilized, with less than 25% of patients receiving target doses in clinical practice. Telemonitoring could provide reliable and real-time physiological data for clinical decision support to facilitate remote GDMT titration.

Objective

This paper aims to present findings from an internal pilot study regarding the effectiveness of remote titration facilitated by telemonitoring.

Methods

A 2-arm randomized controlled pilot trial comparing remote titration versus standard care in a heart function clinic was conducted. Patients were randomized to undergo remote medication titration facilitated by data from a smartphone-based telemonitoring system or standard titration performed during clinic visits.

Results

A total of 42 patients with new-onset (10/42, 24%) and existing (32/42, 76%) heart failure and a mean age of 55.29 (SD 11.28) years were randomized between January and June 2019. Within 6 months of enrollment, 86% (18/21) of patients in the intervention group achieved optimal doses versus 48% (10/21) of patients in the control group. The median time to dose optimization was 11.0 weeks for the intervention group versus 18.8 weeks for the control group. The number of in-person visits in the intervention group was 54.5% lower than in the control group.

Conclusions

The results of this pilot study suggest that remote titration facilitated by telemonitoring has the potential to increase the proportion of patients who achieve optimal GDMT doses, decrease time to dose optimization, and reduce the number of clinic visits. Remote titration may facilitate optimal and efficient titration of patients with heart failure while reducing the burden for patients to attend in-person clinic visits.

Trial Registration

ClinicalTrials.gov NCT04205513; https://clinicaltrials.gov/ct2/show/NCT04205513

International Registered Report Identifier (IRRID)

RR2-10.2196/preprints.19705

Remote Management of Heart Failure: An Overview of Telemonitoring Technologies

Technological advances have enabled increasingly sophisticated attempts to remotely monitor heart failure. This should allow earlier identification of decompensation, better adherence to lifestyle changes and medication and interventions (such as diuretic dosage changes) that reduce the need for hospitalisation. This review discusses telemonitoring approaches in heart failure, and the evidence for their impact. It is not difficult to collect data remotely, but converting more data into better decision-making that improves the outcome of care is challenging. Policy-makers and technology companies are enthusiastic about the potential of digital technologies to transform healthcare and bring expertise to the patient, rather than the other way round, but guideline writers are not yet convinced, due to the lack of consistent findings in randomised trials.

Juguloarterial endothelin-1 gradients after severe traumatic brain injury

BACKGROUND

Endothelin-1 (ET-1) is a potent vasoconstrictor and is thought to be responsible for secondary ischemia and vasogenic edema after traumatic brain injury (TBI). Both CSF and plasma concentrations have been shown to be increased after TBI, but there is little evidence to confirm an intracranial site of production.

METHODS

Using paired arterial and jugular venous bulb sampling, we measured arterial and jugular levels of ET-1 and its precursor, big endothelin (Big ET), and calculated juguloarterial (JA) gradients for the first 5 days post-TBI.

RESULTS

Arterial levels of both Big ET and ET-1 were maximal on day 1 post-TBI, and decreased thereafter (P < 0.05). Arterial levels of Big ET and ET-1 showed correlation across all 5 days of the study (r(2) = 0.25, P < 0.001). While there was no significant JA gradient for Big ET, significant gradients were observed for ET-1 on days 1-4 post-TBI (P < 0.05). There was no correlation between JA gradients for Big ET and ET-1 (r(2) < 0.1, P > 0.9). These data suggest parenchymal production of ET-1 by brain tissue with spill over into the blood, rather than local intraluminal cleavage of Big ET in the cerebral vasculature. Systemic ET-1 levels and JA gradients of ET-1 were unrelated to the injury severity, APACHE II score, Marshall Grade, the presence of subarachnoid or subdural hemorrhage, or eventual outcome.

CONCLUSIONS

These findings confirm the synthesis of Big ET and its cleavage to ET-1 within the brain after TBI. More work is needed to elucidate the pathophysiological role and the outcome impact of ET-1 generation after TBI.

What is the effect of a consultant presence in an acute medical unit?

A cornerstone of the development of acute medicine has been the principle of consultant presence within the acute medical unit (AMU). There is the hypothesis that consultant supervision improves patient care. This view is not currently supported by firm scientific evidence. When Ipswich AMU opened in 2004, there was a consultant presence on some weekdays only. Admission data were collected and assessed with respect to the presence or absence of the consultant. Overall length of stay was significantly lower, by a mean of 1.3 days, when there was a consultant present, and 9% more patients were discharged on the same day of their assessment (95% confidence interval 5.7% to 12.6%, p < 0.001) without affecting readmission or mortality. These results suggest the absence of a consultant leads to fewer same-day discharges and causes the inappropriate admission of patients not needing inpatient management. Further study is required to determine whether these findings are shared by other AMUs.