Diagnostic value of post-return of spontaneous circulation electrocardiogram for selection of candidates for primary percutaneous coronary intervention after out-of-hospital cardiac arrest

Background

Once return of spontaneous circulation (ROSC) is achieved in cardiac arrest (CA) patients (pts), guidelines recommend immediate acquisition of a 12-lead electrocardiogram (ECG) in order to try to identify those with underlying ischemic heart disease that would benefit from an emergent coronary angiography. Nevertheless, post-ROSC ECG findings may be influenced by factors such as drugs used during CPR (e.g., adrenaline) or metabolic state of pts (e.g., lactic acidosis) and therefore its diagnostic value for identification acute coronary lesions has not yet been established.

Objectives

To describe the correlation between post-ROSC ECG findings and acute coronary angiography lesions in out-of-hospital CA (OHCA) pts.

Methods

Retrospective analysis from a prospective database of pts admitted consecutively to the acute cardiac care unit of a tertiary care hospital from September 2006 to April 2019. Post-ROSC ECG of OHCA pts who underwent emergent coronary angiography were blindly and separately classified by 2 cardiologists as follows 1) ST-s elevation, 2) ST-s depression, 3) LBBB, 4) T wave changes/unespecific and 5) normal ECG. If discordant diagnosis, a senior cardiologist made a third and separate analysis. Additionally, coronary lesions were considered to be acute in presence of thrombi or unstable plaque (with or without complete occlusion).

Results

From 412 pts, 211 had an available and interpretable post-ROSC ECG and underwent emergent coronary angiography. Mean age 60±13 years, male sex 183 (86.7%). Correlation between ECG findings and acute coronary lesions are shown in table 1. Pts with ST-s elevation had an underlying acute coronary lesion in 55.2%. Moreover ST-s elevation had a positive predictive value of 84% and sensitivity of 58.8% for identifying acute coronary lesions. Other post-ROSC ECG findings did not significantly associate acute coronary lesions, in fact LBBB had a high negative predictive value for acute lesions.

Conclusion

Among post-ROSC ECG findings, ST-s elevation is significantly associated with acute coronary lesions and when identified, an invasive strategy should be considered as established by current practice guidelines. On the contrary, LBBB rarely associates acute coronary lesions at least in OHCA scenario and when its “new onset” is not specified.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): University Hospital La Paz (Madrid) ECG findings and acute coronary lesions

Arrythmic storm in patients with and without an implantable cardioverter defibrillator

Introduction

Available data on arrhythmic storm (AS) is frequently obtained from retrospective observational series of patients who carry an implantable cardioverter defibrillator (ICD). Therefore, this selection bias limits the evidence regarding mortality and prognosis of patients with AS who do not have an ICD.

Purpose

Describe and compare the epidemiological and clinical characteristics, treatment, and outcomes of patients with and without an ICD, admitted for AS in the Acute Coronary Care Unit.

Methods

Between 2006 and 2020, 187 episodes of AS in 165 patients were identified in two third level hospitals. There were 71 patients without ICD and 116 patients with ICD. Clinical characteristics, treatment and outcome were analysed.

Results

Baseline characteristics are depicted in Figure 1. Risk profile of ICD carriers was worse (they were older, more frequently smokers, had more often hypertension, dyslipidemia, chronic kidney disease and thyroid disturbances, and had worse NYHA class). Known ejection fraction was also worse.

AS aetiology was also different. Myocardial infarction was present only in non ICD carriers (56.3% vs 0, p<0.001) and was the most frequent cause of AS in this group. Ion disturbances were also more common among ICD carriers (60.3% vs 33.6%, p<0.001), but it was the most frequent aetiology of AS in non ICD carriers. Heart failure or cardiogenic shock (36.6% vs 26.7%, p=0.154), infection (7% vs 13.8%, p=0.156) and bradycardia with acquired long QT syndrome (11.3% vs 9.5%, p=0.695) were similar in both groups. There were two episodes of myocarditis among non ICD carriers.

The predominant arrythmia was also different. Ventricular fibrillation was more common in non ICD carriers (43.7% vs 4.3%) while monomorphic ventricular tachycardia was more frequent in ICD carriers (38.8% vs 83.6%, p<0.001).

Non ICD carriers had worse levels of pH (7.30 vs 7.42, p<0.001) and lactate (4.4mmol/L vs 2.0mmol/L, p>0.001) and required inotropic and vasopressor drugs more frequently due to haemodynamic instability (57.7% vs 10.3%, p<0.001), mechanical support with intra-aortic balloon pump (40.8% vs 1.7%, p<0.001), ECMO (8.5% vs 0%, p<0.001), and other mechanical assist devices (5.6% vs 0%, p=0.010), and oral intubation (71.8% vs 17.2%, p<0.001).

Pharmacologic treatment is described in Figure 2.

Non ICD carriers required more frequently percutaneous coronary intervention (59.2% vs 4.3%, p<0.001) and less frequently ventricular ablation (28.2 vs 46.6%, p=0.013). Therapeutic hypothermia was used only in non ICD patients due to out of hospital cardiac arrest (33.8% vs 0%, p<0.001).

In-hospital mortality was higher in non ICD carriers (28.2% vs 11.2%, p=0.003).

Conclusion

Despite a worse cardiovascular profile in ICD carriers, AS is associated with a worse haemodynamic situation and mortality in non ICD carriers, due to different aetiology of the AS and to the absence of protection against sustained arrythmias.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Beca para la Formaciόn e Investigaciόn en Cuidados Críticos Cardiolόgicos concedida por la Asociaciόn de Cardiopatía Isquémica y Cuidados Críticos Cardiolόgicosde la SEC Figure 1. Baseline CharacteristicsFigure 2. Pharmacological treatment

Association between mean arterial pressure and neurological outcome in survivors of a cardiac arrest undergoing targeted temperature management

Background

Besides targeted temperature management (TTM), no other therapeutic strategy has shown to improve neurological outcome in cardiac arrest patients. Recently, it has been suggested that higher levels of mean arterial blood pressure (>90 mmHg) may have a protective neurological effect in this population, yet data is scarce.

Objective

To describe the association between neurological outcomes and MAP during TTM.

Methods

Retrospective study of a prospective database including survivors of a cardiac arrest undergoing TTM and admitted to the acute cardiac care of a tertiary university hospital from September 2007 to July 2020. MAP was recorded from arrival and hourly during TTM. Neurological outcome was graded 3 months after initial event using the Pittsburgh Cerebral Performance Category (CPC) scale and patients were divided classified as follows: Group A patients with CPC of 1 to 2 (good neurological outcome), and group B, with CPC 3 to 5 (poor neurological outcome or death). As CPC 5 comprises patients who have died but whose cause of death may not be related to their neurological condition, we sort to control this potential source of bias, by including a variable of “severe neurological injury”, which includes patients with CPC 3–4 and those CPC 5 who died due to WLST due to poor neurological prognosis/brain death.

Results

A total pf 431 patients were analysed. Baseline and cardiac arrest characteristics are depicted in Table 1. Patients in group B had a higher proportion of non-witnessed cardiac arrest, out-of-hospital cardiac arrest, non-shockable rhythm, and longer time before ROSC. The relation between MAP and neurological outcome is shown in Table 2. The were no differences of MAP in day 1 and 3 between groups. MAP was statistically higher in Group A during day 2 or rewarming phase. Mean MAP during day 1 and 2; and during day 1, 2 and 3 was also significantly higher in group A. However, when same analysis was performed under the variable “severe neurological injury” no statistically significant differences were observed.

Conclusion

There is no association between MAP and neurological outcomes, when true “severe neurological injury” is analysed. Therefore, and until further data is obtained, following actual practical guidelines or avoiding hypotension seems to be the goal in this population, as higher MAP may also have deleterious effects.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): University Hospital La Paz

Arrythmic storm in patients with and without a myocardial infarction

Introduction

Available data on arrhythmic storm (AS) is frequently obtained from retrospective observational series of patients who carry an implantable cardioverter defibrillator or who undergo ablation, and typically, patients with ST-elevation myocardial infarction (STEMI) as the cause of the AS are excluded. Therefore, this selection bias limits the evidence regarding mortality and prognosis of patients with AS due to STEMI.

Purpose

Describe and compare the epidemiological and clinical characteristics, treatment, and outcomes of patients admitted for AS in the Acute Coronary Care Unit due to STEMI and other causes.

Methods

Between 2006 and 2020, 187 episodes of AS in 165 patients were identified in two third level hospitals. There were 40 patients with STEMI and 147 patients with other causes of AS. Clinical characteristics, treatment and outcome were analysed.

Results

Baseline characteristics are depicted in Figure 1. Risk profile of patients without STEMI was worse (they were older, had more often hypertension, and thyroid disturbances, and had worse NYHA class). Patients with STEMI were more frequently smokers. Ejection fraction was higher among STEMI patients.

Predisposing features for AS (apart from myocardial ischemia) were also different. Ion disturbances were more common among STEMI patients (37.4% vs 67.5%, p=0.001). Heart failure or cardiogenic shock (27.9% vs 40.0%, p=0.140), infection (12.2% vs 7.5%, p=0.399) and bradycardia with acquired long QT syndrome (10.2% vs 10.0%, p=0.695) were similar in both groups. There were two episodes of myocarditis in patients without STEMI.

The predominant arrythmia was also different. Ventricular fibrillation was more common in STEMI patients (4.8% vs 72.5%) while monomorphic ventricular tachycardia was more frequent patients without STEMI (80.3% vs 7.5%, p<0.001).

STEMI patients had worse levels of pH (7.40 vs 7.25, p<0.001) and lactate (2.25mmol/L vs 5.56mmol/L, p>0.001) and required inotropics and vasopressors more frequently due to haemodynamic instability (15.0% vs 77.5%, p<0.001), mechanical support with intra-aortic balloon pump (5.4 vs 57.5%, p<0.001), ECMO (2.0% vs 7.5%, p=0.082), and other mechanical assist devices (0 vs 10.0%, p<0.001), and oral intubation (23.8% vs 90.0%, p<0.001).

Pharmacologic treatment is described in Figure 2.

Obviously, STEMI patients required more often percutaneous coronary intervention (8.2% vs 87.5%, p<0.001) and less frequently ventricular ablation (50.3% vs 0, p<0.001). Therapeutic hypothermia was more commonly used in STEMI patients due to out of hospital cardiac arrest (2.0% vs 52.5%, p<0.001).

In-hospital mortality was higher in STEMI patients (11.6% vs 42.5%, p<0.001).

Conclusion

Despite a worse cardiovascular profile in patients without STEMI, AS is associated with a worse haemodynamic situation and mortality in STEMI patients.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Beca para la Formaciόn e Investigaciόn en Cuidados Críticos Cardiolόgicos concedida por la Asociaciόn de Cardiopatía Isquémica y Cuidados Críticos Cardiolόgicosde la SEC Figure 1. Baseline CharacteristicsFigure 2. Pharmacological treatment

Accuracy of 18F-FDG PET/CT in patients with the suspicion of cardiac implantable electronic device infections: good for pocket, not so good for endocarditis

Introduction

The usefulness of 18F-FDG PET/CT in the diagnosis of infective endocarditis (IE) associated with cardiac implantable electronic devices (CIED) is not well established.

Purpose

To assess the diagnostic yield of 18F-FDG PET/CT in patients with suspected CIED infections, placing special emphasis on differentiating between pocket infection (PI) and CIED-IE.

Methods

From 2013 to 2018, all patients (n=63) admitted to a tertiary care hospital with suspected CIED infection were prospectively recruited, undergoing a thorough diagnostic work-up that included blood cultures extraction, transthoracic (TTE) and transoesophageal echocardiography (TEE) and a PET/CT. When device explantation was required, material from the pocket, generator and leads were also cultured. The gold standard for the diagnosis of CIED-IE was a positive lead culture in the absence of PI when percutaneous extraction was performed or a positive culture from a surgically removed lead. In spite of negative lead cultures, the presence of typical TEE images of vegetations in a clinical context of positive blood cultures was also considered as CIED-IE.

Results

After the whole diagnostic process, 14 (22.2%) cases corresponded to isolated PI and 13 (20.6%) were categorized as CIED-IE. Considering radionuclide uptake in the intracardiac portion of the lead, values of sensitivity, specificity and global diagnostic accuracy of PET/CT for CIED-IE were 38.5%, 98.0% and 85.7%, respectively. Positive and negative likelihood ratio values, 19.2 and 0.6 respectively, suggest that a positive PET/CT is much more probable to correspond to a patient with CIED-IE, whereas it is not possible to exclude this diagnosis in case of a negative result. In the case of PI, fair sensitivity (72.2%) and good specificity values (95.6%) were obtained. Extracardiac lead SUVmax and SUVratio in PI were good, with an area under the ROC curve (AUC) of 0.870 and 0.879, respectively. However, semiquantitative analysis was not useful for the diagnosis of CIED-IE.

Conclusions

In patients with suspected CIED infection, the yield of 18F-FDG PET/CT differs depending on the site of infection, showing a very high specificity but poor sensitivity in CIED-IE; so negative studies must be interpreted with caution if the suspicion of CIED-IE is high.

ROC curves SUVmax and SUV ratio for PI

Funding Acknowledgement

Type of funding source: None