Electrocardiologic and Echocardiographic Features of Patients Exposed to Scorpion Bite

Abstract

The purpose of this study is to examine clinical progress and hemodynamic and electrocardi ologic features (QT depression and heart rate variability [HRV]) of patients exposed to a scorpion bite.

Seventeen patients bitten by scorpions, and, as a control group, 15 healthy subjects were included in the study. Standard electrocardiograph (ECG) records, 24-hour Holter-ECG, and Doppler echocardiographic examinations were performed.

Holter ECG indicated sinus tachycardia, sinus bradycardia, paroxysmal supraventricular tachycardia, atrial fibrillation, first-degree and second-degree atrioventricular block not requiring treatment, early atrial beats, and early ventricular beats in the patients at frequen cies of 82%, 12%, 35%, 12%, 8%, 70%, and 47%, respectively.

HRV parameters that reflected parasympathetic activity (SD 35 ±13-43 ±16, RMS-SD: 20 ±9-30 ± 12, high frequency: 7.8 ±2-4.3 ±3, p<0.05) were significantly lower (p<0.05). Low frequency, which especially showed sympathetic activity (LF: 11 ± 13-11 ±23, p>0.05), was similar in both groups. In addition, the LF/HF ratio, which reflected sympathovagal balance, was significantly increased in the patient group (1.5 ±1-3.0 ±2, p = 0.005).

Corrected QT and QT dispersion values were not significantly different with respect to the control (p>0.05).

In the patient group compared to the control, a significant decrease was determined in the proportion of mitral E velocity to mitral A velocity (mEv/mAv), diastolic filling period (DFP), and left ventricular ejection fraction (LVEF), while a significant increase was noticed in pulmonary artery pressure (PAP) (mEv/mAv: 0.9 ±0.4-1.7 ±0.6, DFP: 362 ±8.5-425 ±89, LVEF: 53.1 ±6.7-68.6 ±5.8, PAP: 38.1 ±13-27.2 ±6, p<0.05).

Scorpion bite leads to serious cardiovascular disorders, associated with decreased HRV, decreased systolic and diastolic functions, increased arrhythmic events, and hemodynamic disturbance with sympathetic and parasympathetic balance disturbance.

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