Relevant papers
| Author, date, country | Patient group | Study type | Outcomes | Key results | Study weaknesses |
|---|---|---|---|---|---|
| Hurst et al, 1999, Germany | 49 patients undergoing elective ICD insertion and DFT | Prospective study (2b) | Cardiac biomarkers | 14% of patients had troponin I levels above clinical cut off level | Small study |
| Cardiac biomarkers | troponin I rise related to number of shocks (p=0.04) | ||||
| Joglar et al, 1999, USA | 12 patients undergoing elective ICD insertion and DFT | Prospective cohort study (2b) | Cardiac biomarkers | 50% of patients had troponin I levels above clinical cut off level and all peaked within 12 h | Very small study |
| Rao et al, 1999, USA | 6 patients undergoing ICD insertion and DFT | Prospective study (2b) | Cardiac biomarkers | No troponin I rise | Very small study |
| Schlüter et al, 2001, Germany | 14 patients undergoing elective ICD insertion and DFT | Prospective study (2b) | Cardiac biomarkers | Majority troponin I peaks at 4 h | Very small study |
| Cardiac biomarkers | 21% of patients had troponin I rise above clinical cut off level with ≥2 shocks | ||||
| Hasdemir et al, 2002, USA | 35 patients admitted post spontaneous ICD discharge | Retrospective Study (2b) | Cardiac biomarkers | Troponin rise in 43% of patients without ACS | (1) Small study; (2) no mention if all patients were admitted; (3) possibly late sampling missing some troponin rises |
| Cardiac biomarkers | 22% of Patients with known CAD had proven ACS | ||||
| Cardiac biomarkers | Acute ECG changes present in 25% of patients with clinically interpretable ECGs | ||||
| Cardiac biomarkers | 14% of all patients had ACS | ||||
| Cardiac biomarkers | troponin rise related to number of shocks and delivered energy (p<0.05) | ||||
| Daubert et al, 2008, USA | 719 patients who had ICD implanted | Prospective study (2b) | Death | Inappropriate and appropriate shock causes increased risk of death (AHR 4.08, p<0.01) | Number of shocks not recorded |
| Death | Inappropriate shock alone causes increased risk of death (AHR 2.29, p=0.02) | ||||
| Death | Appropriate shock only causes increased risk of death (AHR 3.36, p<0.01) | ||||
| Poole et al, 2008, USA | 128 patients with heart failure receiving spontaneous ICD discharges | RCT (1b) | Death | Increased risk of death if had discharge of any cause (appropriate/inappropriate) (p≤0.002) | Minor device related data loss |
| Alaiti et al, 2009, USA | Review including 34 studies and 1608 patients | Review | Various | (1) 2.9% of patients had troponin I levels above the normal limit post internal cardioV. (2) 32% of patients had troponin I levels above the normal limit post DFT | Interstudy inconsistencies |
| Blendea et al, 2009, USA | 174 patients who received either spontaneous (66) or induced ICD discharges (108) | Prospective study (2b) | Death | Troponin T rise after ICD discharge is an independent risk factor for mortality (p<0.001) | (1) Study uses troponin T not I; (2) single late troponin level (12–24 h post discharge) |
| Bhavnani et al, 2010, USA | 1372 patients undergoing ICD implantation and DFT with or without subsequent shocks | Retrospective Study (2b) | Hospitalisation for ADHF | Appropriate shock causes increased risk of admission for ADHF (LVEF <35%—AHR 1.66 p<0.002, LVEF>35%—AHR 4.11 p=0.002) | Only first shock included in study—no note if patient had additional shocks |
| Death | Appropriate shock causes increased risk of death (AHR 2.09, p<0.001) | ||||
| Death and hospitalisation for ADHF | Inappropriate shocks did not increase risk of death or hospitalisation from ADHF | ||||
| Francis et al, 2012, USA | 31 patients undergoing first time elective ICD insertion and DFT | Prospective study (2b) | Cardiac biomarkers | Relationship between troponin I and BNP rise post-ICD DFT therefore discharge causes subtle injury and left ventricular dysfunction (p<0.0001) | (1) No control group; (2) only followed for maximum of 12 h; (3) no allied assessment of ventricular function that is, echocardiography; (4) presumably low sensitivity troponin I assay (1.5 ng/mL upper limit normal)?; (5) small study |
| Cardiac biomarkers | One patient had troponin rise above the study's upper limit of normal | ||||
| Toh et al, 2012, Japan | 50 patients undergoing elective ICD insertion and DFT (half LVEF >45%, half LVEF<45%) | Prospective study (2b) | Cardiac biomarkers | No troponin rise above upper limit of normal in either LVEF<45% or LVEF>45% group up to 4 h | (1) Small study; (2) short period of follow-up (only 4 h) |
| Davoodi et al, 2013, Iran | 133 patients undergoing ICD insertion and 130 patients undergoing PPM insertion | Prospective cohort study (2b) | Cardiac biomarkers | Troponin rise from myocardial injury is likely due to DFT rather than device insertion | Inconsistencies between cohorts |
ACS, acute coronary syndrome; ADHF, acute decompensated heart failure; AHR, adjusted HR; BNP, brain natriuretic peptide; CAD, coronary artery disease; DFT, defibrillator threshold testing; ICD, implanted cardioverter defibrillator; LVEF, left ventricular ejection fraction; RCT, randomised controlled trial.