Clinical outcomes of pacemaker implantations before and after cancer diagnosis

Background

Cardiotoxicity caused by anticancer treatment affects cardiac conduction. Clinical outcomes of pacemaker patients with newly diagnosed cancer are insufficiently understood.

Purpose

The aim was to investigate the effect of anticancer therapy on pacemaker properties.

Methods

All patients with pacemaker and confirmed cancer diagnosis treated with chemotherapy at our tertiary university hospital were included in this study. The pacemaker database (containing pacemaker related information) was matched with hospital-wide electronic health records (containing cancer types, comorbidities and echo data). Survival data were retrieved from the Statistics Austria Federal Institute. Clinical and pacemaker data of patients with previously diagnosed cancer requiring pacemaker implantation (Group A) were compared to patients with pre-existing pacemaker followed by cancer diagnosis (Group B).

Results

Out of 972 included patients, 295 patients (30.3%) had the pacemaker implantation after their first cancer diagnosis (Group A), and 677 patients (69.7%) had already a pacemaker before their first cancer diagnosis (Group B). Cancer types are displayed in Figure 1. The following cancer types were associated with increased likelihood for pacemaker implantation after cancer diagnosis (Group A): kidney cancer (OR 2.07, 95% CI 1.12 to 3.83, P=0.02), lymphomas (OR 2.27, 95% CI 1.21 to 4.26, P=0.01), and eye cancer (OR 9.29, 95% CI 1.03 to 83.50, P=0.047). Patients in Group A were older at pacemaker implantation (76.0 years [IQR 68.0–82.2] vs. 72.1 years [IQR 64.3–78.0], P<0.001), and single-chamber pacemakers were less frequent (21.8% vs. 32.1%, P=0.001). Pacemaker implantation due to bradycardic atrial fibrillation was less frequent in Group A (15.6% vs. 21.8%, P=0.03), but implantation due to an “unspecified” indication was increased (20.6% vs. 12.7%, P=0.002). Patients in Group A had lower pacing threshold at baseline but had a stronger increase in pacing threshold during the follow-up as indicated in Table 1. No differences regarding left or right ventricular function, left or right end-diastolic diameter, or mitral or tricuspid regurgitation were detected between the groups. Patients in Group A had smaller left atria (59.7±10.7mm vs. 63.9±24.0mm, P=0.02) and smaller right atria (57.9±10.4mm vs. 61.2±11.8mm, P=0.001). Patients with cancer diagnosis requiring pacemaker had worse 10-year survival (31.2% vs. 51.1%, log-rank P<0.001) as shown in Figure 1.

Conclusion

Kidney cancer, lymphoma, and cancer of the eye were associated with increased probability of pacemaker implantation after cancer diagnosis. The significant increase in pacing threshold in patients undergoing chemotherapy could be associated with chemotherapy-induced cardiotoxicity.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union's Horizon 2020 Future and Emerging Technologies Programme Figure 1. Cancer types and survivalTable 1. Baseline characteristics

Expert consensus on acute management of ventricular arrhythmias - VT network Austria

The Arrhythmia Working Group of the Austrian Society of Cardiology (ÖKG) has set the goal of systematically structuring and organizing the acute care of patients with ventricular arrhythmias (VA), i.e. ventricular tachycardia (VT) or ventricular fibrillation (VF) in Austria. Within a consensus paper, national recommendations on the basic diagnostic work-up of VA (12-lead ECG, medical history, family history, laboratory analyses, echocardiography, search for reversible causes, ICD interrogation), as well as further medical treatment and therapeutic measures (indication of coronary angiography, ablation therapy) are established. Since acute ablation of VT is indicated in the current ESC guidelines as a class IB indication for scar-associated incessant VT or electrical storm (ES; ≥ 3 ICD therapies in 24 h) as well as for ischemic cardiomyopathy (iCMP) with recurrent ICD shocks, organizational measures must be taken to ensure that these guidelines can be implemented. Therefore, a VT network will be established covering all areas in Austria, consisting of primary and secondary VT centers. Organizational aspects of an acute VT network are defined and should subsequently be implemented by the participating hospitals. All electrophysiologic centers in Austria that deal with VT ablation are to be integrated into the network in the medium-term. Centers that co-operate in the network are divided into primary and secondary VT centers according to predefined criteria.

Pacemaker lead-induced progression of primary vs. secondary tricuspid regurgitation

Background

Currently no data are available whether the implantation of right ventricular (RV) pacemaker (PM) lead worsens preexisting primary or secondary (functional due to RV dilatation, RVD) tricuspid regurgitation (TR).

Purpose

The aim of the present retrospective analysis was to assess TR after PM implantation with a RV lead.

Methods

Patients with PM implantation (n=990) were enrolled if they had routine echocardiography including assessment of TR before first implantation and immediately after. RVD and severity of TR were characterized visually. Based on RVD in baseline echocardiography, patients were divided into 2 groups: with primary TR (without preexisting RVD, n=743) or secondary TR (with preexisting RVD, n=243).

Results

Lead-induced worsening of TR was present in both groups (Table 1). Progression from mild/moderate to severe TR was observed in 6.7% of patients with primary TR, compared to 25.6% of patients with secondary TR (P=0.001). Using an ordinal regression model, the probability to progress to severe TR with primary TR was 14.8% (95% CI 11.0%-19.7%), compared to 41.6% (95% CI 40.3%-42.8%) with secondary TR (P<0.001).

Conclusion

Preexisting secondary TR was associated with higher rates of lead-induced progression to severe TR compared to primary TR. Leadless pacing or tricuspid valve clipping post-PM implantation could be an option for patients with preexisting secondary TR and indication for a PM.

Table 1. Patient characteristics.

Funding Acknowledgement

Type of funding source: Public grant(s) – EU funding. Main funding source(s): This study was supported by the European Union's Horizon 2020 Future and Emerging Technologies Programme [Grant number 732170].

State of the art: leadless ventricular pacing : A national expert consensus of the Austrian Society of Cardiology

Background

Cardiac pacing has been shown to improve quality of life and prognosis of patients with bradycardia for almost 60 years. The latest innovation in pacemaker therapy was miniaturization of generators to allow leadless pacing directly in the right ventricle. There is a long history and extensive experience of leadless ventricular pacing in Austria. However, no recommendations of national or international societies for indications and implantation of leadless opposed to transvenous pacing systems have been published so far.

Results

A national expert panel of skilled implanters gives an overview on the two utilized leadless cardiac pacing systems and highlights clinical advantages as well as current knowledge of performance and complication rates of leadless pacing. Furthermore, a national consensus for Austria is presented, based on recent studies and current know-how, specifically including indications for leadless pacing, management of infection, suggestions for qualification, and training of the operators and technical standards.

Conclusions

Leadless pacing systems can be implanted successfully with a low complication rate, if suggestions for indications and technical requirements are followed.

Condensed abstract

An overview of the two utilized leadless cardiac pacing systems is given, specifically highlighting clinical advantages as well as current knowledge of performance and complication rates. Furthermore, a national consensus for Austria is presented, specifically including indications for leadless pacing, management of infection, and suggestions for qualification and technical standards.

Cardiac involvement in patients with sorafenib or sunitinib treatment for metastatic renal cell carcinoma

5110

Background: Tyrosine-kinase inhibitors (TKI) of the VEGF and PDGF-receptor have significant clinical activity in patients with renal cell carcinoma (RCC). These agents target the VHL-hypoxia-inducible gene pathway and lead to inhibition of hypoxia- inducible factor (HIF)-induced gene products. Physiologically, HIF-1 related gene products are important mediators of myocardial response to ischemia, myocardial remodeling, peri-infarct vascularisation and vascular permeability. The aim of this prospective observational study was to investigate clinical and biochemical signs of myocardial damage in patients undergoing TKI-treatment for RCC. Methods: 73 consecutive patients (median age 65, range 44–68) intended for TKI treatment were analyzed for medical history of coronary artery disease (CAD) and risk-factors. Measurements of biochemical markers of cardiac damage (creatine kinase MB -CK-MB- and cardiac troponin T -cTNT-) and electrocardiogram (ECG) were performed before treatment. In patients developing cardiac symptoms during TKI treatment and/or at occurrence of CK-MB or TNT elevations, changes in ECG were analyzed and patients underwent echocardiography. Results: All patients had normal CK-MB and TNT levels at baseline. 17 patients (23%) developed (week 2–32 of treatment) significant CK-MB elevation, (TNT n=5), with clinical symptoms in 7 patients. No patient had uncontrolled hypertension. Detailed ECG’s comparison before and during treatment revealed significant changes in 10 out of 17 patients, such as ST-segment depression or elevation, T-wave changes and symptomatic AV-conduction disturbance, requiring pacemaker-implantation. 3 patients underwent coronary angiography with one patient showing acute coronary artery occlusion and myocardial infarction. 6 out of 17 patients had abnormal findings on echocardiography, such as reduced left ventricular function Conclusions: TKI-induced HIF-inhibition may be associated with severe myocardial damage. The underlying mechanism may not necessarily be caused by overt coronary artery occlusion. ECG-changes and biochemical markers are the most important indicators in the preclinical stage. Therefore, careful cardiac monitoring during TKI-treatment is strongly recommended.

No significant financial relationships to disclose.

Assessment of the safety and efficacy of the novel tetrapeptide ITF-1697 on infarct size after primary PTCA in acute myocardial infarction: a randomised, placebo-controlled pilot trial

OBJECTIVE AND DESIGN

ITF-1697 is a chemically modified LYS-Pro tetrapeptide that corresponds to sequence 113-116 of C-reactive protein. Previous studies have demonstrated significant anti-ischaemic and antithrombotic activity of this tetrapeptide. The aim of this prospective, randomised, double-blind study in patients with acute myocardial infarction undergoing coronary revascularisation was to investigate the safety and efficacy of prolonged intravenous (i.v.) infusion of ITF-1697 at different doses on reduction of infarct size, as assessed by radionuclide imaging.

PATIENTS AND METHODS

Injection of technetium-99m (Tc99m) was followed by injection of ITF-1697 or placebo bolus and 24-hour infusion in patients with acute myocardial infarction. Percutaneous transluminal coronary angioplasty (PTCA) was performed and succeeded by radionuclide imaging. A second Tc99m injection and radionuclide imaging was performed 7 days after the PTCA or at hospital discharge. The primary efficacy variable was set as the ratio between the myocardial salvage (size of the initial perfusion defect minus the final size of the infarct) and the initial area at risk (myocardial salvage index). Twenty-three patients were included in the study protocol, of whom nine were randomised to the ITF-1967 dose 1 group (loading dose 55 microg/kg i.v., infusion 0.5 microg/kg/min for 24 hours), a further nine to the ITF-1697 dose 2 group (loading dose 110 microg/kg i.v., infusion 1.0 microg/kg/min for 24 hours), and the remaining five to the placebo group.

RESULTS

The defined safety variables (adverse events, laboratory parameters, vital signs and clinical outcome) exhibited no relationship to the application of ITF-1697. Comparison of myocardial salvage index revealed no statistical difference within the three groups (p = 0.65). Hypothesis testing on the myocardial salvage as well as the empirical and bias-correct confidence intervals (CIs) revealed significant differences between the ITF-1697 dose 2 group and the placebo group (95% CI 2.75, 18.07).

CONCLUSION

The application of the tetrapeptide ITF-1697 during acute myocardial infarction to reduce infarct size was found to be feasible and safe in this pilot trial.