ABSTRACT
BACKGROUND: Several recent small studies have suggested a causal link between Lyme disease and dilated cardiomyopathy (DCM) by demonstrating the presence of the Borrelia burgdorferi (Bb) genome in the myocardium of patients with recent-onset DCM. The aim of this study was to further investigate the effect of targeted antibiotic treatment of Bb-related recent-onset DCM in a larger cohort of patients. PATIENTS AND METHODS: We performed endomyocardial biopsy (EMB) in 110 individuals (53 ± 11 years, 34 women) with recent-onset unexplained DCM, and detected the Bb genome in 22 (20 %) subjects. Bb-positive patients were subsequently treated with intravenous ceftriaxone for 21 days in addition to conventional heart failure medication. RESULTS: At the 1-year follow-up, a significant improvement in left ventricular (LV) ejection fraction (26 ± 6 vs. 44 ± 12 %; p < 0.01) and a decrease in LV end-diastolic (69 ± 7 vs. 63 ± 11 mm; p < 0.01) and end-systolic (61 ± 9 vs. 52 ± 4 mm; p < 0.01) diameters were documented. Moreover, a significant improvement in heart failure symptoms (NYHA class 3.4 ± 0.6 vs. 1.5 ± 0.7; p < 0.01) was also observed. CONCLUSION: Targeted antibiotic treatment of Bb-related recent-onset DCM in addition to conventional heart failure therapy is associated with favorable cardiac remodeling and improvement of heart failure symptoms.
Subject(s)
Borrelia burgdorferi/isolation & purification , Cardiomyopathy, Dilated/drug therapy , Cardiomyopathy, Dilated/microbiology , Endocarditis, Bacterial/drug therapy , Endocarditis, Bacterial/microbiology , Lyme Disease/drug therapy , Anti-Bacterial Agents/administration & dosage , Cardiomyopathy, Dilated/diagnosis , Cardiotonic Agents/administration & dosage , Ceftriaxone/administration & dosage , Drug Therapy, Combination/methods , Endocarditis, Bacterial/diagnosis , Female , Humans , Injections, Intravenous , Lyme Disease/diagnosis , Lyme Disease/microbiology , Male , Middle Aged , Treatment OutcomeABSTRACT
To assess the feasibility of left atrial flow propagation velocity (LAFPV) measurement and to evaluate the influence of preload alterations on this new parameter of left atrial (LA) reservoir function as compared to conventional echocardiographic indices. 30 healthy volunteers (26 ± 5 years, 20 males) underwent echocardiographic examination at rest, during passive leg lifting and after sublingual administration of nitroglycerine with subsequent Valsalva maneuver. LA reservoir function was assessed by conventional indices including LA expansion index, peak velocity and velocity-time integral of pulmonary venous systolic flow. As well, LAFPV was measured by color M-mode in an apical 4-chamber view as the slope of the transatrial flow wave during LA reservoir phase. LAFPV measurement was feasible in 25 subjects (83%). All conventional parameters of LA reservoir function were significantly altered from resting values by both load-modifying conditions. However, LAPFV was not significantly altered by such maneuvers (228 ± 28 cm s⻹ at rest vs. 238 ± 3 cm s⻹ during leg lifting, P = NS, vs. 218 ± 38 cm s(-1) after nitroglycerin with Valsalva maneuver, P = NS vs. rest, P < 0.01 vs. leg lifting). LAFPV can be measured in a majority of subjects and represents a new, less load-dependent index of LA reservoir function that may more appropriately reflect LA compliance.
Subject(s)
Atrial Function, Left , Echocardiography, Doppler, Color , Echocardiography, Doppler, Pulsed , Hemodynamics , Pulmonary Veins/diagnostic imaging , Adult , Analysis of Variance , Blood Flow Velocity , Compliance , Feasibility Studies , Female , Heart Atria/diagnostic imaging , Heart Atria/physiopathology , Humans , Male , Muscle Contraction , Nitroglycerin/administration & dosage , Observer Variation , Predictive Value of Tests , Pulmonary Veins/physiopathology , Reproducibility of Results , Valsalva Maneuver , Vasodilator Agents/administration & dosage , Young AdultABSTRACT
The time interval (TEa-E) between onsets of early diastolic mitral annular velocity (Ea) and early mitral inflow velocity (E) has been proposed as a new index of left ventricular (LV) relaxation. We aimed to assess the influence of preload changes on this parameter by examining 25 healthy volunteers at rest, after passive leg lifting, and after administration of nitroglycerin combined with Valsalva maneuver. To obtain septal and lateral TEa-E, the time intervals between peak R-wave on electrocardiogram and the onsets of Ea and E were measured in different cardiac cycles. E and Ea were significantly changed by preload manipulations. We did not observe significant changes of TEa-E intervals after leg lifting or after nitroglycerin administration combined with Valsalva maneuver (P = NS). TEa-E was < 0 ms in several subjects using either septal or lateral Ea recordings. We conclude that TEa-E may be load independent in subjects with normal LV systolic and diastolic function as compared to other Doppler parameters. Therefore, this index could be potentially used as a reliable noninvasive parameter of LV relaxation. Nevertheless, even slight differences in cardiac cycle lengths might influence the measurements of TEa-E interval. For that reason, the clinical use of TEa-E seems to be significantly limited because of a wide margin of error in its measurement due to the inability to obtain Doppler recordings during the same cardiac cycle.
