Acute Effects of Implantable Cardioverter‐Defibrillator Shocks on Biomarkers of Myocardial Injury, Apoptosis, Heart Failure, and Systemic Inflammation

Abstract

Background ICD shocks are potentially associated with myocardial injury, altered hemodynamics, apoptosis and inflammatory signaling. Their precise cellular impact can be explored after defibrillation testing (DFT) via biomarkers. We evaluated changes in biomarkers after ICD shocks during DFT. Methods We prospectively enrolled outpatients presenting for first implantation of a cardiac device. Biomarkers indicative of myocardial injury, inflammation and apoptosis were measured before and after implantation, and compared between patients receiving DFT (DFT+) to those not (DFT−). Results Sixty-three patients were enrolled, 40 in the DFT+ group and 23 in the DFT− group. Average levels of troponin I, hsCRP, Calprotectin, NTproBNP, and sFas increased by >50% after cardiac device implantation compared to baseline. Increase in troponin never exceeded 50 fold upper limit of normal (2ng/mL). Troponin trended higher in the DFT+ group at 8 hours (median 0.18 ng/mL, IQR 0.11–0.48) versus the DFT− group (0.10 ng/mL, IQR 0.06–0.28, P=0.0501); NTproBNP had a similar trend (p=0.0581). sFas significantly increased in the DFT+ group from baseline (median 4663 pg/mL, IQR 2908–5679) to 24 hours (5039 pg/mL, IQR 3274–6261; p=0.0338) but not in the DFT− group (p=0.4705). Conclusion DFT testing is associated with acutely increased plasma levels of troponin and sFas, a biomarker of apoptosis, along with a trend towards higher NTproBNP.

Routine DFT testing in patients undergoing ICD implantation does not improve mortality: A systematic review and meta‐analysis

“…One common explanation is that ICD shocks per se can lead to adverse cardiovascular outcomes which may counteract any potential benefit of DFT testing. A recent investigation shows that DFT testing is associated with elevated plasma levels of troponin, NT Pro BNP, and markers of apoptosis . This periprocedural acute myocardial damage triggered by DFT test shocks can further be detrimental if more than one shock is required to terminate induced ventricular fibrillation.…”

“…A recent investigation shows that DFT testing is associated with elevated plasma levels of troponin, NT Pro BNP, and markers of apoptosis. 29 This periprocedural acute myocardial damage triggered by DFT test shocks can further be detrimental if more than one shock is required to terminate induced ventricular fibrillation. It is important to note that time interval between these test shocks may be relevant for defibrillation thresholds and any correlation with cardiac damage and overall prognosis needs to be further investigated.…”

Prognostic importance of serum troponin concentration in patients with an implanted cardioverter‑defibrillator admitted to the emergency department due to electric shock

“…32 The cTnI concentration after ICD implantation without defibrillation testing was related to the number of screw--in lead deployments. 33,34 The group with defibrillation testing showed a higher increase in cTnI concentrations. However, the cTnI concentration in all cases did not exceed 50-fold of the upper limit.…”

Single incision technique for implantation of subcutaneous implantable cardioverter defibrillators

“…Pneumothorax and cardiac perforation, two of the potentially serious complications associated with conventional S‐ICDs, are avoided in S‐ICD implants . Furthermore, because the shocking electrode is not in direct contact with the endocardium, there is less risk for electroporation and potential cardiac damage during shocks delivered by S‐ICD . S‐ICD implantation requires a minimum of two incisions but usually three (one lateral incision and two parasternal incisions), while a conventional transvenous ICD implantation requires only a single incision.…”

“…4,5 Furthermore, because the shocking electrode is not in direct contact with the endocardium, there is less risk for electroporation and potential cardiac damage during shocks delivered by S-ICD. 6,7 S-ICD implantation requires a minimum of two incisions 8 but usually three (one lateral incision and two parasternal incisions), while a conventional transvenous ICD implantation requires only a single incision. As a result, cosmetic appearance of the wounds particularly in females and young patients, discomfort, and risk of infection associated with multiple incisions are of concern.…”