Heterocyclic Drugs from Plants
Rohit Dutt, Anil K. Sharma, Raj K. Keservani, Vandana Garg in Promising Drug Molecules of Natural Origin, 2020
In arrhythmia the heartbeats or rhythms become abnormal. Arrhythmia arises mainly owing to the heart related electrical impulses. If the electrical impulses do not work properly, the heart will become unable to coordinate its beats resulting in irregular rhythms. These impulses can be too fast, too slow, or too erratic causing the heart not to pump blood systematically (About Arrhythmia, 2016). If the heart does not pump blood effectively, the organs might be damaged or completely shut down. Arrhythmias have various types, e.g., tachycardia, bradycardia, and a trial fibrillation. The average heart rate is normally between 60 to 100 beats per minute under normal physical state (All About Heart Rate (Pulse), 2015). Tachycardia refers to a heart rate which is much faster, at or faster than 100 bpm (beats per minute), than the average heart rate (Tachycardia: Fast Heart Rate, 2016). Bradycardia refers to heart rate that is slower that 60 bpm (Bradycardia: Slow Heart Rate, 2016). Atrial fibrillation, also called AFib or AF, is a heartbeat which is irregular/flutters (Atrial Fibrillation, 2016). Arrhythmia occurs if the heart’s natural pacemaker develops an abnormal rhythm or rate, the conduction pathway is disrupted, or if another part takes on the role as the pacemaker.
Heart Rate as a Cardiovascular Risk Factor in Hypertension
Giuseppe Mancia, Guido Grassi, Konstantinos P. Tsioufis, Anna F. Dominiczak, Enrico Agabiti Rosei in Manual of Hypertension of the European Society of Hypertension, 2019
Previous studies have shown that about one-third of young-to-middle-aged patients with hypertension have tachycardia, high cardiac output and hyperkinetic circulation (6). Early pharmacological studies by Julius et al. have documented that this was not due to some individuals having an inherently faster cardiac pacemaker (7). After injection of β-blockers and atropine in two groups of normokinetic and hyperkinetic individuals, the difference in heart rate and cardiac output between the two groups was abolished. Studies based on the assay of plasma norepinephrine or heart rate variability have documented that sympathoadrenergic predominance is a common feature in hyperkinetic hypertension, and microneurographic assessment of efferent postganglionic muscle sympathetic nerve traffic has confirmed that this condition actually reflects increased sympathetic discharge (8,9). Resting heart rate represents the balance of sympathetic and parasympathetic activity and is considered a reliable marker of autonomic nervous system tone (8,9).
The heart
Laurie K. McCorry, Martin M. Zdanowicz, Cynthia Y. Gonnella in Essentials of Human Physiology and Pathophysiology for Pharmacy and Allied Health, 2019
Diastole is the period in the cardiac cycle in which relaxation of the myocardium and ventricular filling take place. In an individual with a resting heart rate of 75 beats/min, the length of the cardiac cycle is 0.8 s and the length of ventricular diastole is 0.5 s. As mentioned in the previous chapter, the EDV is approximately 130 mL and the resulting SV is about 70 mL. Consider the case in which the heart rate is increased. Given that CO is determined by heart rate multiplied by SV, an increase in either of these variables should result in an increase in CO. In general, this is quite true. However, the effect of increased heart rate on CO is limited by its effect on the length of diastole. As the heart rate increases, then the length of the cardiac cycle and, therefore, the length of diastole or the time for filling will decrease. At very high heart rates, this may result in a decrease in ventricular filling or EDV, a decrease in SV, and a decrease in CO. Once again, “the heart can only pump what it gets.” If there is inadequate time for filling, then despite an increase in heart rate, CO will decrease. This explains why the maximal heart rate during exercise is about 185–195 beats/min in all individuals. Beyond this rate, the ventricles are unable to properly fill with blood and the positive effect of increased heart rate on CO is lost.
Effects of 12 weeks of caffeine supplementation and Zumba training on postural balance and cognitive performances in middle-aged women
Published in Health Care for Women International, 2023
Fatma Ben Waer, Rabeb Laatar, Ghada Jouira, Mariam Lahiani, Haithem Rebai, Sonia Sahli
Participants included in this intervention received Zumba exercises for 12 wk at a rate of three 1-h sessions per week on nonconsecutive days. The Zumba sessions were conducted at a fitness center and supervised by professional Zumba trainers. The Zumba training program consisted of continuous dance movements to Latin music with varying intensity level throughout the sessions that were adjusted according to the recommended guidelines for health sport (Brehm et al., 2006). Each training session was initiated with low-intensity movements (warm-up) followed by an increasing intensity throughout the workout (Table 2). Then, in the end, the intensity was gradually reduced (cooling down) (Table 2). Average heart rate during exercise was around 75% of maximum heart rate (Barene et al., 2014). The velocity of the songs (beats per minute) of the main session was increased in two-week intervals.
The Effectiveness of Caudal Block with Low Doses of Dexmedetomidine and Pethidine in Transrectal Prostate Biopsy: Preliminary Results
Published in Journal of Investigative Surgery, 2022
Osman Akyüz, Bahriye Kılıç, Sertan Gündoğan, Müslüm Ergün, Mehmet Nuri Bodakçı, Soner Çoban, Ahmet Hamdi Tefekli, Kamil Çam
The biopsy procedure began when the sensation of cold disappeared in the cold test. The absence of pain perception during prostate biopsy indicated a successful CB. The CB was attempted only once. General anesthesia was initiated in patients for whom a block could not be provided and in those whose NRS score was above 4 during probe and needle entry. These patients were excluded from the study. Biopsy was performed by application of an intrarectal local anesthetic to patients who were not eligible for general anesthesia. The patients were monitored for the side effects of dexmedetomidine in terms of hypotension and bradycardia including systolic and diastolic blood pressures. Additionally, heart rates and oxygen saturation levels were recorded at the 0, 5, 10, 15, 30, 45, 60, and 90-min marks during the procedure, as well as during the postoperative follow-up. Drops in systolic blood pressure below 60 mmHg indicated hypotension. A decrease in heart rate to below 50 bpm indicated bradycardia. All these complications were classified as mild (requiring no further observation and intervention, such as self-limiting hematuria and rectal bleeding, and low-grade pain/dysuria/fever), moderate (requiring only observation or medical treatment, such as hemospermia and urinary infection), severe (requiring intervention, such as massive hematuria, urinary retention, and massive rectal bleeding), or serious (life-threatening conditions, such as sepsis and cardiopulmonary arrest).
Preconceptual leptin levels in gestational diabetes and hypertensive pregnancy
Published in Hypertension in Pregnancy, 2022
Antti Peltokorpi, Lisinen Irina, Viikari Liisa, Kaaja Risto
Mendoza et al. (26) reported higher RHR in pregnant women at <28 gestational weeks as a risk factor for GDM. Our study didn’t find association between pre-pregnancy measured RHR and GDM. Resting heart rate could indicate, although not as a perfect indicator, sympathetic activity especially at heart level. Increased central sympathetic activity as an inducer of increased insulin resistance, seems to prevail after pre-eclamptic pregnancy (27). Positive correlation between resting heart rate and circulating leptin, independent of BMI, have been demonstrated in a study consisting of 2264 males and 2545 females (28). Our results were similar as we found an interesting, yet mild correlation between leptin and RHR in our healthy subjects (Spearman correlation = 0.20; p = 0.015) To be noted, correlation wasn’t significant in GDM group (Spearman correlation = 0.049; p = 0.69), due to which leptin’s inducing effect on RHR and sympathetic activity in association with subsequent GDM cannot be claimed by our results. This raises the question whether individuals with subsequent GDM, had suppressed leptin’s impact on RHR.
Related Knowledge Centers
- Bradycardia
- Carbon Dioxide
- Cardiac Cycle
- Oxygen
- Psychological Stress
- Tachycardia
- Heart
- Body
- Physical Fitness
- Pulse