1Kath. Klinikum Bochum Kardiologie und Rhytmologie Bochum, Deutschland; 2Klinikum der Ruhr-Universität Bochum Medizinische Klinik II, Kardiologie Bochum, Deutschland
Background: In recent years, medical therapy for heart failure with reduced ejection fraction (HFrEF) has improved significantly. Some studies suggest that this also reduces the incidence of life-threatening arrhythmias. The benefit of ICD therapy in reducing arrhythmic death rates in the current era of intensified drug therapy for HFrEF has therefore been questioned.
Methods: All patients who received an ICD for primary prophylactic indication in our hospital from January 2011 to December 2020 were included in this study. The study cohort was divided into patients who received an ICD between 2011 and 2015 (early group) and those who received an ICD between 2016 and 2020 (late group). The primary end point was 1) death from any cause and 2) first adequate ICD therapy (defined as ICD shock or ATP for ventricular fibrillation or sustained ventricular tachycardia).
Results: The study cohort consisted of 323 patients, with 192 patients in the early group and 131 in the late group (Table 1). Follow-up was 5.3 ± 3.3 years in the early group and 2.7 ± 1.7 years in the late group. Patients in the late group received significantly more often angiotensin receptor-neprilysin inhibitors (ARNI) and sodium-glucose- cotransporter 2 (SGLT-2) inhibitors (Table 2). No differences were present with respect to the end point death from any cause (Figure 1) and the combined end point (Figure 2). Adequate ICD therapy occurred in a total of 40 patients in the early group compared to 20 patients in the late group. 7.51 adequate ICD therapies occurred per year in the early group (4 %/year) and 7.43 adequate ICD therapies per year in the late group (5.7%/year) (p = 0.207).
Conclusions: Despite the use of ARNI and SGLT-2 inhibitors in the late group of our study cohort, the annual rate of adequate ICD therapy was not lower than in the early group. Our study suggests that improved drug therapy does not substantially reduce the incidence of life-threatening arrhythmias. Therefore, ICD therapy appears to remain an important component of the treatment of HFrEF patients.
Table 1 Clinical characteristics of study patients (n = 323)
|
|
Early group 2011-2015 (n = 192) |
Late group 2016-2020 (n = 131) |
P value |
|
Age (years) |
67.8 ± 10.3 |
65.9 ± 11.8 |
0.124 |
|
Women (♀), n (%) |
44 (23) |
21 (16) |
0.130 |
|
Left ventricular ejection fraction (%) |
29.9 ± 7.4 |
29.7 ± 7.4 |
0.869 |
|
Creatinine (mg/dL) |
1.21 ± 0.38 |
1.18 ± 0.39 |
0.498 |
|
Nonischemic systolic heart failure, n (%) |
87 (45) |
72 (55) |
0.089 |
|
Medical history | |||
|
Hypertension, n (%) |
146 (76) |
100 (76) |
0.951 |
|
Dyslipidemia, n (%) |
100 (52) |
67 (51) |
0.868 |
|
Diabetes mellitus, n (%) |
73 (38) |
48 (37) |
0.801 |
|
Myocardial infarction, n (%) |
72 (38) |
41 (31) |
0.251 |
|
Coronary artery bypass grafting, n (%) |
43 (22) |
19 (15) |
0.143 |
Table 2 Medication of study patients (n = 323)
|
|
Early group 2011-2015 (n = 192) |
Late group 2016-2020 (n = 131) |
P value |
|
ACEI or ARB or ARNI, n (%) |
177 (92) |
124 (95) |
0.708 |
|
ARB, n (%) |
31 (16) |
26 (20) |
0.416 |
|
ARNI, n (%) |
0 (0) |
39 (30) |
<0.001 |
|
SGLT-2 inhibitors, n (%) |
0 (0) |
10 (8) |
<0.001 |
|
Betablocker, n (%) |
176 (92) |
116 (89) |
0.210 |
|
Aldosterone antagonist, n (%) |
127 (66) |
98 (75) |
0.125 |
|
Loop diuretics, n (%) |
147 (77) |
92 (70) |
0.149 |
ACEI or ARB or ARNI, angiotensin converting enzyme inhibitor or angiotensin receptor blocker angiotensin receptor-neprilysin inhibitor; SGLT-2, Sodium-glucose cotransporter 2
Figure 1: Survival of study patients
Figure 2: Event-free survival (combined endpoint of all-cause death and first adequate ICD-therapy) of study patients