Serious obesity is connected with greater total mortality with a concomitant raised risk of unexpected death. In the latest Framingham research, the risk of unexpected cardiac death with rising weight was observed in the representatives of both genders, and the annual unexpected cardiac mortality rate in fat men and women was estimated at approximately forty times higher than the rate of mysterious cardiac arrest in a matched non-obese population. Obesity and the cardiac autonomic system appear to be importantly connected. A 10 per cent increase in body weight is connected with a reduction in parasympathetic tone, along with an increase in mean heart rate, and conversely, heart rate decreases in the course of losing weight. This fact is of great importance due to the fact that increment in heart rate has been demonstrated as a marker related to increased mortality. Moreover, liquid protein diets have been connected with potentially life threatening arrhythmias due to the fact that higher plasma free fatty acid (FFA) concentrations, that are frequently met along with obesity, can play an essential role in arrhythmogenesis and there may be a connection between FFA concentration and premature ventricular complexes (PVCs), it is of clinical relevance to assess the influence of a high-fat (HIF) diet on autonomic cardiac modulation and arrythmogenicity in serious obesity after weight loss.
Due to the fact that a diet rich in carbohydrates is connected with diminished FFAs, the objective of the current research was to assess the influence of an HIF and high-carbohydrate (HC) diet regimen on both cardiac autonomic nervous system modulation and the occurrence of arrhythmias in reduced-obese persons. Eight severely obese participants (BMI higher than or equal to 40 kg/[m.sub.2]) have undergone a three-month weight loss program followed by a three-month reduced-weight maintenance regimen. After that, each of the participants was admitted for an inpatient period of seventeen days on two separate occasions. A high-carbohydrate (60 per cent) or high-fat (55 per cent) diet of proper energy content for weight maintenance was recommended in the course of each inpatient phase. Heart rate variability was derived from a 24-hour Holter monitoring system in all participants in the course of their inpatient stay. Cardiac Holter monitoring was carried out at three occasions, including the 2nd night of a two overnight calorimetry chamber stay.
The diet regimen resulted in a 10 per cent reduction of weight. There was no considerable alteration in systolic and diastolic blood pressure, arrhythmias, glucose, insulin, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, respiratory exchange ratio, and resting energy expenditure between experiments. Mean heart rate was reduced after weight loss in comparison to baseline. After weight loss, there was a rise in the parasympathetic indices of heart rate variability showing and also rise in cardiac vagal modulation.
The results of the current research indicate that weight loss is connected with considerable improvement in autonomic cardiac modulation through enhancement of parasympathetic modulation, which is clinically translated into a decline in heart rate.
