Different characteristics of heart failure due to pump failure and bradyarrhythmia

Abstract

BackgroundHeart failure (HF) can be caused by left ventricular (LV) pump failure as well as by bradyarrhythmias. Hemodynamic differences between HF by LV pump failure and that by bradyarrhythmia have not been fully investigated. We hypothesized that HF by LV pump failure could be associated with both reduced cardiac output (CO) and increased LV filling pressure due to associated LV diastolic dysfunction, whereas HF by bradyarrhythmia could be associated with reduced CO but only modestly increased LV filling pressure due to the absence of LV diastolic dysfunction.MethodsIn 39 patients with HF by LV pump failure (LV ejection fraction <35 %), 24 with HF by bradyarrhythmia, and 22 normal controls, LV volume, ejection fraction, stroke volume, left atrial volume, and early diastolic mitral valve flow to tissue annular velocity ratio (E/E′) were measured by echocardiography.ResultsCompared to patients with HF by LV pump failure, those with HF by bradyarrhythmia had significantly lower heart rates, less LV dilatation, preserved LV ejection fraction, preserved stroke volume, similarly reduced cardiac index (1.8 ± 0.4 vs. 1.6 ± 0.4 L/min/m2, n.s.), preserved LV diastolic function (E′) (4.4 ± 2.1 vs. 7.1 ± 2.9 cm/s, p < 0.001), less dilated end-systolic LA volume, and preserved E/E′ (24 ± 10 vs. 13 ± 7, p < 0.001).ConclusionsHF by LV pump failure is characterized by both significantly reduced CO and increased LV filling pressure, whereas HF by bradyarrhythmia is characterized by a similar reduction in CO but only modestly increased LV filling pressure.

Clinically Significant High-Grade AV Block as a Reversible Cause for Acute Kidney Injury in Hospitalized Patients—A Propensity Score Matched Cohort

“…Potential mechanisms for the impact of HGAVB on renal function start from the obvious–the direct hemodynamic effects of HGAVB on circulation [ 2 , 3 ]: as heart rate decreases, the cardiovascular system loses its ability to control CO by tachycardia and can only compensate by increasing stroke volume which is limited, especially in patients with previous cardiovascular diseases [ 23 ]. The decrease in CO can, by itself, reduce glomerular filtration rate, as one is derived from the other.…”

Case report: severe bradycardia, a reversible cause of “Cardio-Renal-Cerebral Syndrome”

“…Patients with ADHF and type 1 CRS have usually poor outcomes especially when accompanied by severe hypotension that is not reversible [6]. But low CO, that is generally believed to occur secondary to a decreased LVEF, results sometimes from bradyarrhythmia [7, 8]. Patients with HF due to left ventricular (LV) pump failure and those with HF due to bradyarrhythmia have similar reductions in CO.…”

“…Patients with HF due to left ventricular (LV) pump failure and those with HF due to bradyarrhythmia have similar reductions in CO. However the stroke volume is reduced in patients with LV pump failure whereas it is increased in bradyarhythmia [7]. This increase in stroke volume is mandatory to ensure the hemodynamic stability of the patient with bradycardia.…”

Regulation of sinus node pacemaking and atrioventricular node conduction by HCN channels in health and disease

“…Iwataki et al (Iwataki et al, 2015) compared 39 patients with a mean heart rate of 8417 beats/min and heart failure, which they attributed to left ventricular pump failure, with 24 patients with a mean heart rate of 395 beats/min and heart failure, which they attributed to the bradyarrhythmia; in both groups there was a decrease in cardiac output and increase in left ventricle filling pressure (the latter was only modest in the bradyarrthmic patients). However, the study of Iwataki et al (Iwataki et al, 2015) is inconclusive: although Iwataki et al (Iwataki et al, 2015) attributed the heart failure in the bradycardic patients to the bradyarrhythmia, it is also possible that the bradyarrhythmia is a consequence of the heart failure. Penton et al (Penton et al, 1956) studied 251 AV (i.e.…”