P2568Larger vectorcardiographic QRS area is associated with increased risk of heart failure development among left bundle branch block patients: a register-based cohort study

Background

QRS morphology including left bundle branch block (LBBB) and duration remain the most widely used surrogate markers in the 12-lead electrocardiogram (ECG) for assessing ventricular dyssynchrony and predicting future burden of heart failure (HF) and cardiovascular mortality. However, the vectorcardiographic QRS area has recently been proposed and evidence suggest that this marker may more accurately predict HF development.

Purpose

The aim of this study was to investigate the association between vectorcardiographic QRS area and risk of HF development in LBBB patients.

Methods

From 2001–2015, the Copenhagen General Practitioners' Laboratory was used to identify patients with a first-time LBBB ECG (QRS>120 ms; LBBB morphology), from which QRS area was derived using the Kors transformation method and grouped into quartiles. Outcome was a composite of HF diagnosis, redeemed prescriptions of loop diuretics, or death from HF. Death from other causes was accounted for as a competing risk.

Results

We included a total of 2843 LBBB patients who were free of heart failure (median age, 70 years; female, 58%; ischemic heart disease, 9%). QRS area quartiles comprised Q1, 67–158 μVs; Q2, 159–189 μVs; Q3, 190–228 μVs; and Q4, 229–739 μVs. During 6-month, 1-year, and 5-year follow-up, 9%, 12%, and 28% of patients reached the combined HF endpoint, and 1%, 2%, and 8% of patients died from other causes, respectively (Figure 1). After multivariable adjustment, the highest QRS area quartile, Q4, was associated with increased HF risk (adjusted hazard ratio, 1.64; 95% confidence interval, 1.35–2.00) compared with the lowest quartile, Q1. We did not observe any significant increase in HF risk for remaining quartiles (Q2 or Q3 vs. Q1).

Figure 1

Conclusions

Among primary care patients with newly discovered LBBB, a large vectorcardiographic QRS area (229–739 μVs) is associated with increased risk of developing the incident, combined HF endpoint. This indicates that the QRS area derived using the Kors method may serve as a valuable prognostic marker when assessing risk of HF in patients with LBBB.

2285Increased risk of out-of-hospital cardiac arrest associated with psychiatric disorders

Introduction

Patients with psychiatric disorders are at high risk of cardiovascular morbidity and mortality; yet, the risk of out-of-hospital cardiac arrest (OHCA) compared to the general population remains unknown.

Purpose

We investigated whether the presence and severity of different psychiatric disorders were associated with a higher risk of OHCA.

Methods

We conducted a case-control study matching all adult patients with OHCA of presumed cardiac cause between 2001 and 2014 with up to nine controls from the entire Danish population on age, sex and ischemic heart disease (IHD). Patients with psychiatric disorders were identified using in- and out-patient hospital diagnoses – both primary and secondary - before index date. We identified six mutually exclusive psychiatric disorders that were separately examined: personality disorders, anxiety, substance-related mental disorders, depression, bipolar disorder and schizophrenia. The risk of OHCA associated with the six psychiatric disorders was evaluated by conditional logistic regression adjusting for comorbidities, concomitant pharmacotherapy, socioeconomic status and marital status.

Results

We included 32,447 OHCA cases matched with 291,999 controls from the general population. Overall, the median age was 72 years, 67% were male and 29% had IHD prior to index date. All the six psychiatric disorders examined were more common among cases than controls; depression was the most common psychiatric disorders in both groups: 5.0% among cases and 2.8% among controls. Concurrently, all six psychiatric disorders were associated with significantly higher odds of OHCA: personality disorders (odds ratio (OR) 1.30 [95% confidence interval (CI) 1.06–1.60], anxiety OR 1.26 [95% CI 1.15–1.39], substance induced-mental disorders OR 2.36 [95% CI 2.17–2.57], depression OR 1.27 [95% CI 1.19–1.35], bipolar disorder OR 1.32 [95% CI 1.16–1.50] and schizophrenia OR 1.80 [95% CI 1.58–2.05] (Figure). The association persisted unaffected when we studied psychiatric patients neither exposed to antipsychotics nor to antidepressants. We observed a trend towards a stronger association when we stratified according to the severity of the psychiatric disorder (Figure). Severe disorders where classified as at least one hospitalization for the specific psychiatric illness as primary diagnosis during the five years prior to index date.

Conclusions

Common psychiatric disorders including personality disorders, anxiety, substance-related mental disorders, depression, bipolar disorder and schizophrenia are significantly associated with higher odds of OHCA. These findings provide a rationale for early cardiovascular risk factor screening and, potentially, management among psychiatric patients to identify patients at high risk of OHCA.

Acknowledgement/Funding

ESCAPE-NET project

P4135Patients with psychiatric disorders have reduced chances of receiving optimal post-arrest cardiovascular management

Introduction

Healthcare disparities between patients with and without a known psychiatric disorder have been documented worldwide. Whether these inequalities also apply to a life-threatening condition such as out-of-hospital cardiac arrest (OHCA) is unknown

Purpose

We aimed to investigate differences in selected in-hospital cardiovascular procedures following OHCA between patients with and without psychiatric disorders.

Methods

We identified adult patients with OHCA of presumed cardiac cause admitted to hospital following OHCA (2001–2015). Patients with psychiatric disorders were identified using hospital diagnoses or redeemed prescriptions for psychotropic drugs and studied both as a single group and separately (three subgroups: severe mental illness [SMI], minor psychiatric disorders, patients who redeemed psychotropic drugs). We calculated age- and gender-standardized incidence rates (SIRs), and relative incidence-rate-ratio (IRR), of cardiovascular procedures during admission post-OHCA in patients with and without psychiatric disorders. Differences in 30-day and 1-year survival were assessed by multiple logistic regression in the overall population and among 2-day survivors who received acute coronary angiography (CAG).

Results

We included 7,288 hospitalized OHCA-patients: 1505 (22.8%) had a psychiatric disorder. Compared with patients without psychiatric disorders, patients with psychiatric disorders had lower SIRs for acute CAG (≤1 days post-OHCA) (IRR 0.51 [95% confidence interval, CI, 0.45–0.57]) (Figure), subacute CAG (2–30 days post-OHCA) (IRR 0.40, [95% CI 0.30–0.52]) and ICD-implantation (IRR 0.67, [95% CI 0.48–0.97]). Lower rates of acute and subacute CAG were still present in subanalyses only including patients with initial shockable rhythm, among those with return of spontaneous circulation upon hospital-arrival and regardless of Charlson score and socioeconomic status. Notably, the difference in CAG-rates between the two groups increased in the recent years. Conversely, we did not detect differences in coronary revascularization (encompassing coronary artery bypass graft and percutaneous coronary intervention) among CAG-patients (IRR 1.11 [95% CI 0.94–1.30]) (Figure). Patients with psychiatric disorders showed lower survival following OHCA, even among 2-day survivors who received acute CAG: odds (OR) of 30-day survival 0.63 (95% CI, 0.48–0.83) and 1-year survival 0.61 (95% CI 0.46–0.81).

Conclusions

Patients with psychiatric disorders had half the probability of receiving acute and subacute CAG and lower chances of ICD-implantation compared to non-psychiatric patients, but, among CAG-patients, same probability of coronary revascularization. Moreover, their survival was lower irrespective of acute angiographic procedures. Our findings show disparities that demand urgent action considering the large burden of cardiovascular morbidity and mortality in patients with psychiatric disorders.

Acknowledgement/Funding

ESCAPE-NET

P6562The relationship between serum potassium concentrations and electrocardiographic characteristics in 163,547 individuals from primary care

Aims

Potassium disturbances are common and associated with increased morbidity and mortality, even in patients without prior cardiovascular disease. We examined six electrocardiographic (ECG) measures and their association to serum potassium levels.

Methods and results

From the Copenhagen General Practitioners' Laboratory, we identified 163,547 individuals aged ≥16 years with a first available ECG and a concomitant serum potassium measurement during 2001–2011. Restricted cubic splines curves showed a non-linear relationship between potassium and the Fridericia corrected QT (QTcF) interval, T-wave amplitude, morphology combination score (MCS), PR interval, P-wave amplitude and duration. Therefore, potassium was stratified in two intervals K: 2.0–4.1 mmol/L and 4.2–6.0 mmol/L for further analyses. Within the low potassium range, we observed: QTcF was 12.5 ms longer for each mmol/L decrease in potassium (p<0.0001); T-wave amplitude was 55.1 μV lower for each mmol/L decrease in potassium (p<0.0001); and MCS was 0.09 higher per mmol/L decrease in potassium (p<0.001). Moreover, P-wave duration and PR interval were prolonged by 3.1 and 3.3 ms for each mmol/L decrease in potassium (p<0.0001), respectively. Within the lowest potassium range (2.0–4.1 mmol/L) P-wave amplitude was 10.7 μV higher for each mmol/L decrease in potassium (p<0.0001). Within the high potassium range associations with the above-mentioned ECG parameters were much weaker.

Restricted cubic splines on adjusted lin

Conclusion

The association of potassium with six commonly measured ECG parameters was non-linear. Strong associations between ECG abnormalities and potassium were seen among individuals with lower potassium levels (≤4.1 mmol/L).

Acknowledgement/Funding

None

Exposure to selective serotonin reuptake inhibitors in utero and early elementary school outcomes

OBJECTIVE

Data on special education in offspring exposed to selective serotonin reuptake inhibitors (SSRIs) in utero are lacking. We examined associations of in utero SSRI exposure with special education needs and delayed elementary school start.

METHODS

A population-based case-cohort study using Danish nationwide birth and prescription registry data from 2005 to 2008. Follow-up ends during 2011-2015 to capture special education needs during and delayed entry to the first elementary school year. Cases were in utero SSRI-exposed offspring. Cohort-controls were SSRI-unexposed offspring of mothers previously on SSRIs. We reported odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for relevant potential confounders.

RESULTS

Of 117 475 first-incident non-multiple pregnancy births, 3314 were SSRI-exposed, and 3536 were unexposed. Among SSRI-exposed offspring, 3.2% (n = 98) had special school needs vs. 2.4% (n = 77) in unexposed offspring, P-value=0.048. Correspondingly, 12.3% (n = 383) among SSRI-exposed children had delayed school entry vs. 9.4% (n = 308) in unexposed offspring, P-value < 0.001. Adjusted OR for the association with special school needs was 1.12 (95% CI 0.82-1.55; P-value = 0.48) and 1.38 (95% CI 0.90-2.13; P-value = 0.14) for exposure in all three trimesters. The corresponding adjusted ORs for delayed school entry were 1.17 (95% CI 0.99-1.38; P-value = 0.073) and 1.40 (95% CI 1.11-1.76; P-value = 0.004).

CONCLUSION

In utero SSRI exposure in all three trimesters was associated with delayed elementary school start but not special education needs.

Adverse cardiac events in out-patients initiating clozapine treatment: a nationwide register-based study

OBJECTIVE

Using national Danish registers, we estimated rates of clozapine-associated cardiac adverse events. Rates of undiagnosed myocarditis were estimated by exploring causes of death after clozapine initiation.

METHOD

Through nationwide health registers, we identified all out-patients initiating antipsychotic treatment (January 1, 1996-January 1, 2015). Rates of clozapine-associated myocarditis and pericarditis within 2 months from clozapine initiation and rates of cardiomyopathy within 1-2 years from clozapine initiation were compared to rates for other antipsychotics. Mortality within 2 months from clozapine initiation was extracted.

RESULTS

Three thousand two hundred and sixty-two patients of a total 7932 patients initiated clozapine as out-patients (41.12%). One patient (0.03%) developed myocarditis, and no patients developed pericarditis within 2 months from clozapine initiation. Two (0.06%) and four patients (0.12%) developed cardiomyopathy within 1 and 2 years respectively. Rates were similar for other antipsychotics. Twenty-six patients died within 2 months from clozapine initiation. Pneumonia (23.08%) and stroke (11.54%) were the main causes of death. We estimated the maximum rate of clozapine-associated fatal myocarditis to 0.28%.

CONCLUSION

Cardiac adverse effects in Danish out-patients initiating clozapine treatment are extremely rare and these rates appear to be comparable to those observed for other antipsychotic drugs.