Systolic Blood Pressure Recovery Research Articles

English

BACKGROUND: Hypertension (HTN) is a common public health challenge. Early detection and appropriate treatment is the solution to this problem. Normotensives with parental history of hypertension have higher risk of developing this disorder. Such normotensives have greater cardiovascular reactivity to exercise. OBJECTIVES: To identify abnormal heart rate (HR) and blood pressure (BP) responses during exercise recovery in young adult normotensives with and without parental history of hypertension. MATERIAL AND METHODS: The present study was conducted in the clinical laboratory of Department of Physiology, MNR Medical College, Sangereaddy, Andhra Pradesh during May 25th 2011 to July 25th 2011 to observe the cardiovascular response (HR & BP) to exercise in healthy young adults using Harvard step test and to compare the influence of parental history of hypertension on it. 100 healthy young adults were selected in the age group of 18-22 year from the student population of our college. They were divided into 2 major groups (each major group consisting of 50 subjects) based on history of hypertension in their parents. The students having parental history of hypertension in at least one parent were taken in study group. Those students having both normotensive parents were taken as controls for comparison. Each major group was further divided into 2 minor groups based on gender (each minor group consisting of 25 subjects).Statistical Analysis: Data analysis between the groups was done with using SPSS software for Windows, Version 15. Independent-Sample T-test was used to find significant difference between the subjects with and without parental history of HTN. Statistical significance was set at p<0.05. RESULTS AND CONCLUSION: In male subjects having family history of hypertension the HR at rest and at 3 rd , 6 th , 9 th & 12 th minute of exercise recovery; immediate recovery systolic blood pressure (SBP) and diastolic blood pressure (DBP) at 3 rd minute of recovery were significantly higher compared to age and sex matched subjects without family history of hypertension. Whereas in females only HR at the immediate recovery period was significantly higher in study subjects having parental history of hypertension compared to controls.

Exercise-Induced Muscle Vasodilatation and Treadmill Exercise Test Responses in Individuals without Overt Heart Disease

Background: The beneficial effects of exercise on cardiovascular health may be related to the improvement in several physiologic pathways, including peripheral vascular function. The aim of this study was to evaluate the relationship between cardiovascular responses during the treadmill exercise test and exercise-induced muscle vasodilatation in individuals without overt heart disease. Methods: The study included 796 asymptomatic subjects (431 females and 365 males) without overt heart disease. We evaluated the heart rate (chronotropic reserve and heart rate recovery), blood pressure (maximum systolic and diastolic blood pressure as well as systolic blood pressure recovery) and exercise capacity during symptom-limited treadmill exercise testing. Exercise-induced muscle vasodilatation was studied with venous occlusion plethysmography and estimated by forearm blood flow and vascular conductance responses during a 3-min handgrip maneuver. Results: Forearm blood flow increase during the handgrip exercise was positively associated with heart rate recovery during treadmill exercise testing (p < 0.001). Forearm vascular conductance increase during the handgrip exercise was inversely associated with exercise diastolic blood pressure during exercise treadmill testing (p = 0.038). No significant association was found between exercise capacity and exercise-induced muscle vasodilation. Conclusion: In a sample of individuals without overt heart disease, exercise-induced muscle vasodilatation was associated with heart rate and blood pressure responses during treadmill exercise testing, but was not associated with exercise capacity. These findings suggest that favorable hemodynamic and chronotropic responses are associated with better vasodilator capacity, but exercise capacity does not predict muscle vasodilatation.

Impaired Systolic Blood Pressure Recovery Directly After Standing Predicts Mortality in Older Falls Clinic Patients

Normally, standing up causes a blood pressure (BP) drop within 15 seconds, followed by recovery to baseline driven by BP control mechanisms. The prognostic value of this initial BP drop, but also of the recovery hereafter, is unknown. The aim of this study was to examine the prognostic value of these BP characteristics in response to standing. In a retrospective cohort study of 238 consecutive patients visiting our falls outpatient clinic, we examined the relation between all-cause mortality and BP decline and recovery directly after active standing up with Cox proportional hazards analyses. Of 238 patients (mean age 78.4 ± 7.8 years), during a median follow-up of 21.0 months, 36 (15%) patients died. Neither absolute nor relative (%) initial BP drop after standing predicted mortality. In contrast, the magnitude of BP recovery 40-60 seconds after standing was associated with mortality, even after adjustment for age, comorbidity, and other baseline characteristics. When systolic BP had recovered to less than 80% of prestanding baseline after 60 seconds of standing, this was a powerful independent predictor of mortality (hazard ratio: 3.00; 95% confidence interval 1.17-7.68). Failure to recover from BP decline in the first minute after active standing up is associated with excess mortality in falls clinic patients. A recovery of systolic BP to less than 80% of baseline after 60 seconds may be used as an easily available cardiovascular marker for increased mortality risk in older falls clinic patients.

Normal reactions to orthostatic stress in Rett syndrome

The aim of this study was to investigate orthostatic reactions in females with Rett syndrome (RTT), and also whether the severity of the syndrome had an impact on autonomic reactions. Based on signs of impaired function of the central autonomic system found in RTT, it could be suspected that orthostatic reactions were affected. The orthostatic reactions in 21 females with RTT and 14 normally developed females matched by age were investigated when they rose from a sitting position, and during standing for 3 min. Reactions of the heart, the blood pressure and the time for recovery of systolic blood pressure, were studied in real time, heartbeat by heartbeat, simultaneously. There was no difference between participants with RTT and the normally developed controls regarding general orthostatic reactions (heart rate, systolic and diastolic blood pressure, and mean arterial pressure) when getting up from a sitting position, and when standing erect for 3 min. In the specific immediate response by the heart to standing up, the 30:15 ratio, significantly lower values were found for females with RTT. In the RTT group, the maximum fall of systolic blood pressure showed a tendency to a larger decrease, and the initial decrease in systolic blood pressure was significantly faster. The time for recovery of systolic blood pressure from standing erect did not differ between groups. At baseline the females with RTT had significantly lower systolic blood pressure and a tendency to a higher heart rate. The results do not indicate any autonomic limitations for people with RTT in getting up from a sitting position and standing. The participants with RTT had normal orthostatic reactions indicated by the heart and blood pressure responses when standing erect for 3min. A faster initial drop in systolic blood pressure in people with RTT was notable.

Caffeine Ingestion and Intense Resistance Training Minimize Postexercise Hypotension in Normotensive and Prehypertensive Men

The primary aim of the study was to compare changes in blood pressure (BP) in normotensive and prehypertensive men completing resistance exercise following caffeine ingestion. Normotensive (n = 7) and hypertensive men (n = 7) ingested caffeine (6 mg.kg−1) or placebo 1 h preexercise, then completed four sets of bench press, leg press, lat pull-down, and shoulder press at 70%–80% one repetition maximum (1-RM). Heart rate (HR) and BP were measured preexercise, during exercise, and for 75 min postexercise. Caffeine increased (p < 0.05) resting, exercise, and recovery systolic BP, yet had no effect on HR (p = 0.16) or diastolic BP (p = 0.10). HR and BP were significantly higher (p < 0.05) in prehypertensive men versus normotensives. Postexercise hypotension did not occur in either treatment, suggesting that intense resistance training with or without caffeine intake may mitigate the BP-lowering effect of resistance exercise.

Kounis–Zavras syndrome presenting with ventricular arrhythmias and cardiogenic shock

In this case report we describe a case of the Kounis–Zavras syndrome (coincidental occurrence of chest pain and allergic reactions accompanied by clinical and laboratory findings of cardiac ischemia). A 34-year-old woman presented to the emergency unit with severe chest pain from 2h. She reported a medical history of asthma. On arrival, her heart rate was 125beats/min and her systolic blood pressure (SBP) was 70mmHg. A repeated electrocardiogram displayed dynamic changes with ST-segment elevation in D1-aVL leads and ST-segment depression in infero-posterior leads. Two episodes of ventricular fibrillation were observed. The coronary artery angiography showed multivessel coronary vasospasms. Intracoronary nitroglycerin was used to alleviate the coronary vasospasms. Contemporaneously, the patient's husband came to the hospital reporting a history of ketorolac consumption some hours before the onset of the acute event for headache symptoms. This crucial information permitted us to suppose it was a case of allergic myocardial infarction during anaphylactic shock due to ketorolac. Betametasone, chlorphenamine, and ranitidine were administered and progressively a full recovery of SBP and of clinical status was observed.<Learning objective: Allergic myocardial infarction (Kounis-Zavras syndrome) is a complex acute coronary syndrome which requires rapid treatment decisions. Most of the information on this syndrome comes from case reports or small case series. It should be considered in young, healthy patients when they develop acute coronary syndrome after administration of potentially allergic agent. The treatment should both dilate coronary vessels and suppress the allergic reaction (steroids, antihistamines, fluid resuscitation, oxygen, nitrates, calcium channel blockers).>

Cardiovascular Reactivity to and Recovery from Stressful Tasks Following a Mindfulness Analog in College Students with a Family History of Hypertension

Ninety-seven (97) undergraduates with a family history of hypertension participated in a study that evaluated the effects of a brief mindfulness-induction on cardiovascular reactivity and recovery to two stressors. Participants were randomized to either a mindfulness-induction or control condition and were then exposed to the cold pressor task (CPT) followed by the mirror-tracing task (MT). Blood pressure and heart rate were measured at baseline and postinduction, as well as during and immediately following each stressor. There were no group differences in reactivity to either stressor. Participants in the mindfulness-analog condition experienced significantly greater latency to systolic blood pressure recovery following the CPT and a tendency toward greater latency to diastolic blood pressure recovery, although these findings were not replicated with the MT task. These results are contrary to what was hypothesized and to the anecdotal evidence available regarding effects of comprehensive mindfulness interventions on reactivity. The findings are discussed with respect to purported mechanisms of mindfulness and learning theory.

South Asians Have Elevated Postexercise Blood Pressure and Myocardial Oxygen Consumption Compared to Europeans Despite Equivalent Resting Pressure

BackgroundStroke mortality rate is higher in South Asians than in Europeans, despite equivalent or lower resting blood pressure (BP). Elevated recovery BP after exercise predicts stroke, independently of resting values. We hypothesized that South Asians would have adverse postexercise hemodynamics and sought explanations for this.Methods and ResultsA population-based sample of 147 European and 145 South Asian middle-aged men and women performed the Dundee 3-minute step test. Cardiovascular risk factors were measured. BP, heart rate, and rate–pressure product, a measure of myocardial oxygen consumption, were compared. With 90% power and 5% significance, we could detect a difference of 0.38 of a standard deviation in any outcome measure. Resting systolic BP was similar in South Asians (144 mm Hg) and Europeans (142 mm Hg) (P=0.2), as was exercise BP (P=0.4). However, recovery systolic BP at 3 minutes after exercise was higher in South Asians by 4.3 mm Hg (95% confidence interval [CI], 0.2 to 8.3 mm Hg; P=0.04). This effect persisted when adjusted for exercise BP and work effort (5.4 mm Hg [95% CI, 2.2 to 8.7 mm Hg; P=0.001]). Adjustment for baroreflex insensitivity and greater aortic stiffness in South Asians contributes greatly to attenuating this ethnic difference (1.9 mm Hg [95% CI, −0.9 to 4.6 mm Hg; P=0.4]). Similarly, rate–pressure product recovery after exercise was impaired in South Asians by 735 mm Hg/min (95% CI, 137 to 1334 mm Hg/min; P=0.02); again, adjustment for baroreflex insensitivity and aortic stiffness attenuated this difference (261 mm Hg/min [95% CI, −39 to 561 mm Hg/min; P=0.3]).ConclusionPostexercise recovery of BP and rate–pressure product is impaired in South Asians compared to Europeans even though resting and exercise BP are similar. This is associated with the autonomic dysfunction and aortic stiffness in South Asians. (J Am Heart Assoc. 2012;1:e000281 doi: 10.1161/JAHA.111.000281.)

Autonomic neural control of the cardiovascular system in patients with Behçet’s disease in the absence of neurological involvement

Behçet's disease (BD) is a chronic multi-system disease presenting with recurrent oral and genital ulceration, and relapsing uveitis. Heart rate recovery (HRR) after exercise is a marker of parasympathetic activity. A delayed recovery of systolic blood pressure (SBP) after exercise might reflect sympathetic hyperactivity. The analysis of variations in heart rate has also been used to determine the balance between sympathetic and vagal nerve activities in the heart. Our objective was to determine HRR, the SBP response to exercise and heart rate variability (HRV) in patients with BD in the absence of neurological involvement. The study population consisted of 32 patients with BD and 30 healthy controls who were matched with respect to age, sex, and physical activity. Heart rate recovery was calculated as the difference between heart rate at peak exercise and heart rate at 1, 2, and 3 min of recovery. Blood pressure recovery indexes were determined by dividing the systolic blood pressure at 2 and 3 min in recovery to the systolic blood pressure at peak exercise. In patients with BD, mean HRR at 1 min (HRR1) were not significantly different than that of controls (21 ± 7 vs 20 ± 7 bpm, p = 0.50). Although, resting mean SBP of patients with BD was higher than controls (121 ± 13 vs 115 ± 12 mmHg, p = 0.039), the SBP recovery indices of the patients with BD at 2 and 3 min were similar to those of controls (0.84 ± 0.07 vs 0.84 ± 0.09, p = 0.89 and 0.78 ± 0.09 vs 0.78 ± 0.08, p = 0.93, respectively). Both time domain and frequency domain parameters of patients with BD were similar to that of controls. This study shows that the patients with BD have normal HRR1 and normal SBP response to exercise and normal HRV. These findings might suggest unaltered autonomic neural control of the cardiovascular system in this disorder in the absence of neurological involvement.

Fish consumption and cardiovascular response during mental stress

BackgroundFrequent fish consumption is related to a lower risk of coronary heart disease. However, the physiological mechanisms underlying this cardioprotective effect are as yet unknown. We therefore examined certain cardiovascular physiological variables of fish eaters during rest, whilst conducting mental arithmetic, and during recovery.FindingsThe participants were 12 fish eaters (eating baked fish more than 3–4 times/week) and 13 controls (eating fish less than 1–2 times/week). Analysis of the collected data revealed that heart rate, blood pressure, and pulse wave velocity were significantly lower and pre-ejection period and baroreflex sensitivity were significantly higher in the fish eaters than in the controls during both rest and mental arithmetic, and that systolic and mean blood pressure recovery from mental arithmetic were faster in the fish eaters than in the controls.ConclusionsThese findings suggest a possible physiological mechanism that may explain why frequent fish consumption reduces coronary heart disease risk.

Effects of two different quadriceps strengthening exercise approaches on cardiovascular fitness in healthy female subjects: A single blind randomized study

There are limited number of documents showing the relations between cardiovascular fitness and muscle strength. This study aimed to determine the effects of two different quadriceps strengthening exercise approaches on cardiovascular fitness in healthy female subjects. Forty female university students participated in this study on a voluntary basis. The participants were randomly assigned to do either isokinetic exercise (IE) or progressive resistive exercise (PRE) in two different groups. Both training schemes were performed three times a week for a period of two weeks. The subjects were given a maximum symptom limited exercise test on a treadmill before and after (each) training period. Total exercise duration increased and Borg scale level decreased significantly after training in the two groups (p < 0.05). Maximal systolic blood pressure, recovery heart rate, and recovery diastolic blood pressure decreased significantly in the IE Group (p < 0.05). Resting and recovery systolic blood pressure decreased significantly in the PRE Group (p < 0.05). Compared to PRE group, improvement for Borg Scale level, recovery heart rate and recovery diastolic blood pressure were more obvious in IE Group (p < 0.05). This study demonstrated that both quadriceps strengthening methods have displayed improvements in cardiovascular fitness. Further research with larger sample groups may need to be carried out.

Autonomic reactivity and hypothalamic pituitary adrenal axis dysregulation in spouses of Oklahoma City bombing survivors 7 years after the attack

ObjectiveThe objective of this exploratory pilot study was to examine autonomic reactivity and hypothalamic pituitary adrenal axis dysregulation in spouses of highly exposed survivors of the 1995 Oklahoma City bombing. MethodsThis study compared psychiatric diagnoses and biological stress markers (physiological reactivity and cortisol measures) in spouses of bombing survivors and matched community participants. Spouses were recruited through bombing survivors who participated in prior studies. Individuals with medical illnesses and those taking psychotropic medications that would confound biological stress measures were excluded. The final sample included 15 spouses and 15 community participants. The primary outcome measures were psychiatric diagnoses assessed with the Diagnostic Interview Schedule for DSM-IV (DIS-IV). Biological stress markers were physiological reactivity and recovery in heart rate and blood pressure responses to a trauma interview and cortisol (morning, afternoon, and diurnal variation). ResultsCompared to the community participants, spouses evidenced greater reactivity in heart rate, systolic blood pressure, and diastolic blood pressure; delayed recovery in systolic blood pressure; and higher afternoon salivary cortisol. ConclusionsThe results support the need for further research in this area to clarify post-disaster effects on biological stress measures in the spouses of survivors and the potential significance of these effects and to address the needs of this important population which may be overlooked in recovery efforts.

Association between genetic variants of the ADD1 and GNB3 genes and blood pressure response to the cold pressor test in a Chinese Han population: the GenSalt Study

Genetic factors influence blood pressure (BP) response to the cold pressor test (CPT), which is a phenotype related to hypertension risk. We examined the association between variants of the α-adducin (ADD1) and guanine nucleotide binding protein (G protein) β-polypeptide 3 (GNB3) genes and BP response to the CPT. A total of 1998 Han Chinese participants from the Genetic Epidemiology Network of Salt Sensitivity completed the CPT. The area under the curve (AUC) above the baseline BP during the CPT was used to measure the BP response. Twelve single-nucleotide polymorphisms (SNPs) of the ADD1 and GNB3 genes were selected and genotyped. Both single-marker and haplotype association analyses were conducted using linear mixed models. The rs17833172 and rs3775067 SNPs of the ADD1 gene and the rs4963516 SNP of the GNB3 gene were significantly associated with the BP response to CPT, even after adjusting for multiple testing. For the ADD1 gene, the AA genotype of SNP rs17833172 was associated with lower systolic BP (SBP) reactivity (P<0.0001) and faster BP recovery (P=0.0003). The TT genotype of rs3775067 was associated with slower SBP recovery (P=0.004). For the GNB3 gene, the C allele of SNP rs4963516 was associated with faster diastolic BP recovery (P=0.002) and smaller overall AUC (P=0.003). Haplotype analysis indicated that the CCGC haplotype of ADD1 constructed by rs1263359, rs3775067, rs4961 and rs4963 was significantly associated with the BP response to CPT. These data suggest that genetic variants of the ADD1 and GNB3 genes may have important roles in BP response to the CPT. Future studies aimed at replicating these novel findings are warranted.

Respiratory and Immune Response to Maximal Physical Exertion following Exposure to Secondhand Smoke in Healthy Adults

We assessed the cardiorespiratory and immune response to physical exertion following secondhand smoke (SHS) exposure through a randomized crossover experiment. Data were obtained from 16 (8 women) non-smoking adults during and following a maximal oxygen uptake cycling protocol administered at baseline and at 0-, 1-, and 3- hours following 1-hour of SHS set at bar/restaurant carbon monoxide levels. We found that SHS was associated with a 12% decrease in maximum power output, an 8.2% reduction in maximal oxygen consumption, a 6% increase in perceived exertion, and a 6.7% decrease in time to exhaustion (P<0.05). Moreover, at 0-hours almost all respiratory and immune variables measured were adversely affected (P<0.05). For instance, FEV1 values at 0-hours dropped by 17.4%, while TNF-α increased by 90.1% (P<0.05). At 3-hours mean values of cotinine, perceived exertion and recovery systolic blood pressure in both sexes, IL4, TNF-α and IFN-γ in men, as well as FEV1/FVC, percent predicted FEV1, respiratory rate, and tidal volume in women remained different compared to baseline (P<0.05). It is concluded that a 1-hour of SHS at bar/restaurant levels adversely affects the cardiorespiratory and immune response to maximal physical exertion in healthy nonsmokers for at least three hours following SHS.

Exercise training enhances autonomic function after acute myocardial infarction: A randomized controlled study

IntroductionHeart rate recovery, defined as the fall in heart rate during the first minute after exercise, is an indicator of autonomic function, and has been found to be an independent predictor of mortality after acute myocardial infarction. Exercise training has several well-known benefits in terms of cardiorespiratory fitness, modifiable cardiovascular risk factors and prognosis after acute coronary events. However, there are no randomized controlled studies in the literature evaluating the effects of exercise training per se, controlling for changes in medication and diet, on heart rate recovery. Thus, this study aims to assess the effects of exercise training on autonomic function in coronary artery disease patients recovering from acute myocardial infarction. MethodsThirty-eight patients following a first acute myocardial infarction participated in this prospective randomized clinical trial. Patients were randomized into two groups: exercise training or control. The exercise group participated in an 8-week aerobic exercise program, while the control received standard medical care and follow-up. Changes in hemodynamics at rest and at peak exercise (heart rate, systolic and diastolic blood pressure, and rate pressure product), dietary intake, cardiorespiratory fitness, and heart rate recovery were assessed. ResultsMedication and diet remained unchanged in both groups during the study period. The exercise-training group improved resting hemodynamics, particularly resting heart rate (from 68.0±9.2 to 62.6±8.7bpm, p=0.030) and systolic blood pressure (from 135±7.1 to 125.6±11.3mmHg, p=0.012), cardiorespiratory fitness (from 30.8±7.8 to 33.9±8.3ml/min/kg, p=0.016), and heart rate recovery (from 20±6 to 24±5bpm, p=0.007). No significant changes were observed in the control group. ConclusionsExercise training improved autonomic function, assessed by heart rate recovery, resting heart rate and systolic blood pressure, in the absence of changes in diet or medication.

Exercise training enhances autonomic function after acute myocardial infarction: A randomized controlled study

IntroductionHeart rate recovery, defined as the fall in heart rate during the first minute after exercise, is an indicator of autonomic function, and has been found to be an independent predictor of mortality after acute myocardial infarction. Exercise training has several well-known benefits in terms of cardiorespiratory fitness, modifiable cardiovascular risk factors and prognosis after acute coronary events. However, there are no randomized controlled studies in the literature evaluating the effects of exercise training per se, controlling for changes in medication and diet, on heart rate recovery. Thus, this study aims to assess the effects of exercise training on autonomic function in coronary artery disease patients recovering from acute myocardial infarction. MethodsThirty-eight patients following a first acute myocardial infarction participated in this prospective randomized clinical trial. Patients were randomized into two groups: exercise training or control. The exercise group participated in an 8-week aerobic exercise program, while the control received standard medical care and follow-up. Changes in hemodynamics at rest and at peak exercise (heart rate, systolic and diastolic blood pressure, and rate pressure product), dietary intake, cardiorespiratory fitness, and heart rate recovery were assessed. ResultsMedication and diet remained unchanged in both groups during the study period. The exercise-training group improved resting hemodynamics, particularly resting heart rate (from 68.0±9.2 to 62.6±8.7bpm, p=0.030) and systolic blood pressure (from 135±7.1 to 125.6±11.3mmHg, p=0.012), cardiorespiratory fitness (from 30.8±7.8 to 33.9±8.3ml/min/kg, p=0.016), and heart rate recovery (from 20±6 to 24±5bpm, p=0.007). No significant changes were observed in the control group. ConclusionsExercise training improved autonomic function, assessed by heart rate recovery, resting heart rate and systolic blood pressure, in the absence of changes in diet or medication.

Comparison of haemodynamic responses to intubation: Flexible fibreoptic bronchoscope versus bonfils rigid intubation endoscope

Background:The flexible fibreoptic bronchoscope and bonfils rigid intubation endoscope are being widely used for difficult intubations.Methods:The haemodynamic response to intubation under general anaesthesia was studied in 60 adult female patients who were intubated using either flexible fibreoptic bronchoscope or bonfils rigid intubation endoscope (30 in each group). Non-invasive blood pressure and heart rate (HR) was recorded before induction of anaesthesia, immediately after induction, at the time of intubation and, thereafter, every minute for the next 5 min. The product of HR and systolic blood pressure (rate pressure product) at every point of time was also calculated.Statistical Analyses:Graph pad prism, 5.0 statistical software, independent t test and repeated measure ANOVA test were used.Results:Both bonfils rigid intubation endoscope and flexible fibreoptic bronchoscope required a similar time (less than 1 min) for orotracheal intubation. After intubation, there was a significant increase in HR, blood pressure and rate pressure product (P<0.001) in both the groups compared with the baseline and post-induction values. There was no significant difference in HR, blood pressure and rate pressure product at any of the measuring points or in their maximum values during observation between the two groups. The time required for recovery of systolic blood pressure and HR to post-induction value (±10%) was not significantly different between the two groups (more than 2 min).Conclusion:In female adults under general anaesthesia, bonfils rigid intubation endoscope and flexible fibreoptic bronchoscope require a similar time for successful orotracheal intubation and cause a similar magnitude of haemodynamic response.

A rare sign of ischemia during exercise ECG: PR interval lengthening in the recovery period

Exercise electrocardiography (ECG) is one of the most commonly utilized tests in cardiology. Despite the drawbacks, exercise ECG is widely preferred due to low cost, standardization, and strong prognostic information. A prolonged PR interval during recovery has recently been proposed as an indicator of mortality. Herein, we report an interesting case of a patient who presented with the complaint of exertional dyspnea and exhibited PR lengthening during the recovery period on the exercise ECG. The patient had a PR interval of 240 ms before exercise, which decreased to 160 ms at peak stress. However, during recovery, the PR interval prolonged gradually, reaching 320 ms at the second minute and persisting at that length until the end of the recovery period. The patient achieved 87% of the age predicted maximum heart rate, and experienced non-disabling shortness of breath and a pressure sensation in the chest, with no apparent ST segment depression. Recovery parameters, including heart rate recovery and systolic blood pressure recovery, were also within normal limits. The patient underwent coronary angiography with the suspicion of CAD which revealed severe multi-vessel disease. This rare case emphasizes the importance of PR lengthening in the recovery period as a sign of severe ischemia, in addition to other signs, such as prominent ST-segment changes, chronotropic incompetence, impaired hemodynamic response, and poor exercise capacity during stress ECG evaluation.

Effects of Working Memory Load on Performance and Cardiovascular Activity in Younger and Older Workers

Working memory (WM) declines with ageing, and this may cause problems in older workers who have to do complex work requiring WM. We tested the assumption that an increase in WM load negatively affects performance and results in impaired cardiovascular adaptation to changing task demands in older workers relative to younger ones. Thirty-three younger (29 ± 3years) and 32 older (55 ± 3years) workers had to perform a visual 0-back (low WM load) and 2-back (high WM load) task. Heart rate (HR), heart rate variability (HRV), beat-to-beat blood pressure (BP) and baroreflex were registered. In the high WM load condition, older adults responded more slowly and less accurately than younger adults, while no age effects in the low WM load condition were found. Older workers showed a higher systolic blood pressure (SBP) reactivity to high WM load as well as a diminished post-task recovery of SBP and HRV than younger workers. Factor analysis demonstrated a close relationship between HR, baroreflex and HRV and their modulation by a common factor ("vagal tone") in the younger group. By contrast, HR was more related to the "sympathetic" factor in the older group. The data suggest that older workers as compared with younger ones are impaired in tasks requiring WM, which is accompanied by enhanced cardiovascular "costs" in terms of increased SBP and reduced vagal control over HR.

Non-Hypertensive Patients with Prolonged P-Wave Indices Have Higher Blood Pressure Response to Exercise Stress Test

Background/Objectives: Hypertension during exercise has been linked to future hypertension. Prolonged P-wave indices (PWI) has also been associated with prehypertension. We aim to compare exercise stress test parameters in non-hypertensives with normal and prolonged PWI. Methods: Non-hypertensive patients above 18 years without known heart disease and negative ECG stress test were studied. 12-lead ECG at a paper speed of 25 mm/s and 1 mV/cm were recorded. An electronic caliper and magnifier were used to measure PWI. Patients were classified into normal or prolonged P-wave duration and dispersion. Stress test parameters such as systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) at rest, peak, and recovery; target heart rate achieved; exercise duration; METs; and rate pressure products were recorded. Results: 76 patients were eligible with mean age of 43.77±12.16. 46% were male. 36% and 47% had prolonged P-wave duration and dispersion respectively. Patients with prolonged P-wave duration have higher peak DBP than those with normal duration (91.54±10.07 versus 84.69±9.60, P=0.006). Recovery SBP and DBP were also significantly higher. Among patients with prolonged P wave dispersion, recovery SBP and DBP were significantly higher compared with normal subjects (P<0.05). Conclusion: Prolonged PWI were associated with higher blood pressure response to exercise stress test. Further investigations may provide more conclusive evidences in the role of PWI as novel markers of future hypertension.