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Aim of the present study was to investigate the diagnostic yield of the lactate-stress-test in unselected patients with suspected respiratory-chain disorder (RCD). Serum lactate was determined before, during and after a 15-minute, constant 30W workload on a bicycle in 48 controls and 160 patients with suspected RCD. 122 had definite RCD 38 neurological disorders other than RCD. The sensitivity, specificity, positive predictive value, negative predictive value and pre-test likelihood of the test was 69, 74, 89, 42 and 76 % respectively. In conclusion, the lactate-stress-test proved a powerful tool to assess impaired oxidative metabolism in RCDs. [ABSTRACT FROM AUTHOR]

Background: This study assessed the accuracy of exercise methoxy isobutyl isonitrile (MIBI) single photon emission computed tomography (SPECT) in the evaluation of the extent of coronary artery disease (CAD) in patients with an earlier myocardial infarction.Methods and Results: We studied 135 patients (mean age, 57+/-10 years; 115 men) at a mean of 4.1 years (median, 1 year) after myocardial infarction with symptom-limited bicycle exercise stress and rest MIBI SPECT imaging. Coronary angiography was performed within 3 months. Significant CAD was defined as a stenosis of 50% or larger in luminal diameter in 1 or more major coronary arteries. Myocardial perfusion defects (fixed, reversible, or both) were detected in 107 of the 113 patients with significant CAD and in 10 of the 22 patients without significant CAD (sensitivity, 95%; CI, 91 to 99; specificity, 55%; CI, 46 to 63, and accuracy, 88%; CI, 82 to 94). The specificity rate increased to 73% (CI, 65 to 80) by using only reversible perfusion defects as a means of predicting CAD. Reversible perfusion abnormalities were more frequent in patients with multivessel CAD than in patients with single-vessel CAD (51 of 64 [80%] vs. 27 of 49 [55%], P<.01). Myocardial perfusion abnormalities in 2 vascular regions, which is suggestive of multivessel CAD, were detected in 35 of the 64 patients with and in 9 of the 71 patients without multivessel CAD (sensitivity for detecting CAD in more than one vascular region, 55%; CI, 46 to 63, specificity, 87%; CI, 81 to 93, and accuracy, 72%; CI, 64 to 80). The sensitivity rates for the diagnosis of left anterior descending coronary artery, left circumflex, and right coronary artery based on any defect were 80%, 70%, and 63%, respectively. The corresponding specificity rates were 70%, 76%, and 73%, respectively.Conclusions: Exercise MIBI SPECT imaging is an accurate method for the diagnosis and localization of CAD in patients with an earlier myocardial infarction. The technique provides a high specificity and moderate sensitivity for the diagnosis of multivessel CAD on the basis of myocardial perfusion abnormalities in more than 1 vascular region. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the relative importance of graft occlusions and progression of atherosclerosis in coronary arteries as causes of the occurrence of angina pectoris and impairment of physical performance 5 years after coronary artery bypass surgery.Design: A 5-year follow-up study.Setting: University hospital in south-western Finland.Subjects: Altogether, 174 consecutive electively operated bypass patients.Main Outcome Measures: Serial clinical evaluation and bicycle exercise tests (pre-operatively, at 6 months, and at 1 and 5 years). Quantitative coronary angiography pre-operatively and 5 years after the surgery.Results: Subjects with patent grafts had fewer angina pectoris symptoms at the 5-year follow-up (24 vs. 52%, P = 0.001) and were treated less frequently with long-acting nitrates (3 vs. 15%, P = 0.037) than subjects with graft occlusions. Fewer of them were in classes II-III of the functional classification of the Canadian Cardiovascular Society (39 vs. 74%, P = 0.001). The exercise test was interrupted less often because of chest pain (23 vs. 41%, P = 0.03) and improvement in exercise test variables during the follow-up period was significantly greater in subjects with patent grafts (P<0.002). Amongst patients without graft occlusions, those with new > or =50% diameter stenoses in coronary arteries were more often in functional classes II-III (59 vs. 32%, P = 0.03) than those without new stenoses, but the groups were similar with respect to angina pectoris and exercise tests variables. In patients with graft occlusions, those with and without new > or =50% diameter stenoses were similar with respect to functional class, angina pectoris and exercise test variables.Conclusions: Angina pectoris and impairment of physical capacity 5 years after coronary artery bypass grafting are mainly due to occlusion of bypass grafts and not to progression of atherosclerosis in coronary arteries. [ABSTRACT FROM AUTHOR]

Background: Age characteristics of patients undergoing various types of stress tests are important because of differences in clinical background and exercise performance between the young and elderly. Adverse effects of pharmacologic agents are known to be more common in the elderly, who are less able to perform vigorous exercise stress testing. We investigated the clinical background, performance characteristics, and complication rate of various stress tests in younger (<75 years old) and elderly (>75 years old) patient populations.Methods: A total of 3412 patients (2796 younger, 616 elderly) underwent 5 types of stress tests with (1) technetium-99m sestamibi (MIBI) single photon emission computed tomography: symptom-limited exercise (Ex, 1598 younger, 173 elderly), (2) dipyridamole infusion (0.14 mg/kg/min, 4 minutes) without exercise (D, 260 younger, 114 elderly), (3) with exercise (DEx, 339 younger, 112 elderly), (4) adenosine infusion (0.14 mg/kg/min, 5 minutes) without exercise (A, 253 younger, 101 elderly), and (5) with exercise (AEx, 346 younger, 116 elderly).Results: Sixty-seven percent of patients in the younger population were able to achieve 85% of the maximum predicted heart rate, whereas 54% of the elderly reached this level of exercise. No patient had life-threatening complications. In both the younger and elderly groups, chest discomfort, feelings of impending syncope, flushing, and fall in blood pressure occurred less frequently in DEx than D and in AEx than A. Sinus bradycardia occurred less frequently in AEx than A in the younger (1.2% vs 4.3%, P < .05) and elderly groups (0.9% vs 6.9%, P < .05). Atrioventricular block was less frequent in AEx than A in the younger group (3.2% vs 7.9%, P < .05) but not so in the elderly group (13.0% vs 17.8%, not significant). The frequency of ischemic electrocardiographic changes in DEx and AEx was very similar to that of Ex in both the younger and elderly groups, although ischemic electrocardiographic changes in D and A are known to be less frequent.Conclusion: Of the elderly group who were judged to be fit to exercise to 85% of maximum predicted heart rate, nearly half failed to reach this level. In contrast, the younger patients were able to achieve this level in 67% of tests. Supplementation with modest exercise reduced most of the pharmacologically related adverse effects. The elderly group was not protected from atrioventricular block as effectively as the younger group by additional exercise in the adenosine stress test. Ischemic electrocardiographic changes in the pharmacologic stress test were as frequent as in the exercise stress test when modest supplementary exercise was added to the pharmacologic protocol. There were no deaths, myocardial infarction, or other major complications. These observations suggest that exercise and pharmacologic stress tests are safe in the elderly, including those patients more than 75 years old. [ABSTRACT FROM AUTHOR]

With two different questionnaires, we analyzed the feeling of well-being during dual chamber pacing mode and VVI mode in 25 randomly selected patients, mean age 66.7 years (range 22-84). All patients had high degree AV block and received either a DDD pacemaker (23 patients) or a VDD pacemaker. Under each pacing mode exercise tests were performed as well. Questionnaire 1 was answered during DDD or VDD mode. According to questionnaire 1, 76% of the patients remembered their symptoms before PM implantation. Eighty-two percent of the patients felt an improvement of their symptoms after the installation of the pacemaker. Questionnaire 2 was answered after a three-week period of VVI pacing. Fifty-six of the patients indicated a deterioration of their general conditions, 56% of the patients noted dizziness, 58% dyspnea, 40% reduced effort tolerance, and 22% a sleep disturbance. After a change to dual-chamber pacing, general well-being was better in 74% of the patients, dyspnea was noted in only 15%, effort tolerance was improved in 61%, and sleep was undisturbed in 97%. The physical work capacity (expressed as a product of Watts multiplied by minutes) tested on a bicycle ergometer was 400 ± 190 Wmin in VVI mode and 414 ± 272 Wmin in DDD/VDD mode (p = ns). The double products were 14,600 ± 4,934 and 22,066 ± 5,585 (p < 0.05), respectively. We conclude that dual-chamber pacing leads to a significant improvement in the quality of life for patients with symptomatic AV block. [ABSTRACT FROM AUTHOR]

Dobutamine pharmacological stress testing in conjunction with technetium-99m methoxyisobutylisonitrile single-photon emission tomography (MIBI SPET) may be a useful alternative to convential exercise stress MIBI SPET for the detection and localisation of coronary artery stenoses. Therefore, 35 patients with stenoses (≥ 50% diameter reduction) of one or more coronary arteries were selected for dobutamine MIBI SPET. Each patient underwent MIBI injection at rest and during dobutamine infusion with incremental doses (5, 10, 15 and 20 μg kg min). A conventional exercise stress test (EST) was performed in all patients. Peak double product during steady-state dobutamine infusion (18 200 ± 4200 mmHg min) was lower ( P = 0.0001) than during EST (21 700 ± 4900 mmHg min). Image quality was good in all but one patient, who had to be excluded from data analysis due to excessive hepatobiliary MIBI activity. Dobutamine-induced perfusion abnormalities were observed in 30/34 MIBI SPET studies, resulting in an overall detection rate for coronary artery disease of 88%. A pathological EST was observed in 23/34 patients (68%). The detection rate of individual coronary artery stenoses was 85% (28/33) for stenosess with a severe diameter reduction (>70%) and 50% (12/24) for stenoses with a moderate diameter reduction (≥ 50-70%). In particular, sensitivity and specificity for the detection of moderate and severe stenoses (≥ 50%) were 75%/100% for left anterior descending, 67%/95% for left circumflex and 67%/69% for right coronary artery stenoses. Dobutamine MIBI SPET is a well-tolerated, non-exercise-dependent test for detection and localisation of haemodynamically significant coronary artery stenoses. The use of dobutamine allows a stepwise increase in pharmacological stress similar to EST and is especially useful in patients who are unable to exercise. [ABSTRACT FROM AUTHOR]

The objective of the study was to develop a non-invasive method for the quantitative evaluation of cardiovascular performance and ventricular-arterial (VA) coupling during varying physiological states. VA-coupling was represented by the ratio between the arterial and ventricular elastances - Ea/Ees. Approximate indices of the relative change of Ees and VA-coupling during stress were developed and tested. These indices can be evaluated directly from noninvasive measurements of ejection fraction values (for VA-coupling) and measurements of stroke volumes and systolic and diastolic arterial pressures (for Ees). Additional relative indices can be evaluated from these data (e.g., stroke work, cardiac output) to yield a complete representation of the cardiovascular response to stress. The present methodology was applied to assess the exercise stress response in healthy subjects (H, n = 8) and in patients with left ventricular dysfunction ( n = 24). Left ventricular volumes were determined by nuclear angiography and arterial pressures were measured non-invasively by a new, validated method. Using published data obtained invasively, we found that the relative indices of Ees and VA-coupling showed a high correlation with the invasive ones ( r > 0.8, P < 0.01). The patients were subgrouped by their maximal exercise capacitance (P2 − 50W, P3 − 75W). At rest, the two patient groups had similar ejection fraction values (45 ± 15% and 48 ± 16%), which were significantly different from those of the healthy subjects (66 ± 7%, P < 0.05). During stress, a larger increase in stroke work and cardiac output was found in the healthy subjects. All three groups showed similar relative increases in Ees and heart rate, but relative Ea increased in P2 and decreased in H, while the opposite was found for the end-diastolic volume. The relative VA-coupling index in P2 was significantly larger than that in P3 and H ( P < 0.05). The present non-invasively based indices can be used to quantitatively monitor the individual cardiovascular response to stress testing or drug interventions and to evaluate the importance of VAcoupling in the clinical setting. [ABSTRACT FROM AUTHOR]

Objective: To determine whether evaluation and management of males and females differ after presentation to the emergency department with acute chest pain.Design: Prospective cohort study with follow-up at 1 month.Setting: Urban teaching hospital.Patients: The study population included 1,411 patients who were 30 years of age or older who visited the emergency department with acute chest pain from October 1990 through May 1992. These 1,411 patients represent 69% of the 2,056 patients approached for consent. The utilization of exercise stress testing as outpatients was measured for a subset of 954 patients who were interviewed at 1 month after their presentation.Measurements/main Results: After controlling for clinical and nonclinical predictors, women were less likely to be admitted to the hospital (adjusted odds ratio [OR] 0.68; 95% confidence interval [CI] 0.47, 0.99). Among the 954 patients with 1-month follow-up, women were less likely than men to undergo an exercise stress test during the first month after presentation, with borderline statistical significance after adjusting for the interaction between gender and admission to the hospital (adjusted OR 0.30; 95% CI 0.09, 1.0). Among the patients who were admitted to the hospital, women were as likely as men to undergo exercise stress testing (adjusted OR 0.81; 95% CI 0.57, 1.2) but were less likely to undergo cardiac catheterization (adjusted OR 0.44; 95% CI 0.25, 0.80).Conclusions: Gender-based differences in management may occur at several stages in the evaluation of patients with acute chest pain. Observed differences in use of invasive procedures between men and women may be due in part to lower rates of exercise test use and admission to the hospital for evaluation of acute chest pain. [ABSTRACT FROM AUTHOR]

Dobutamine pharmacological stress testing in conjunction with gradient-echo magnetic resonance imaging (MRI) may be a useful tool for the assessment of haemodynamically significant coronary artery stenoses. Therefore, 28 patients without previous myocardial infarction but significant proximal stenoses (≥70% diameter stenosis) of one or more coronary arteries were selected for dobutamine-MRI. Each patient underwent MRJ at rest and during incremental dobutamine infusion (5, 10, 15 and 20 μg. kg. min). Additionally, all patients were submitted to exercise stress electrocardiography (EST). A total of 72 segments per patient obtained from identical short axis and transverse tomograms at rest and during dobutamine infusion were evaluated by two observers. Each segment was graded as normal, hypokinetic, akinetic or dyskinetic. Dobutamine-MRI was considered pathological if segmental wall motion deteriorated by at least one grade after dobutamine infusion. For comparison with coronary angiography, segmental wall motion gradings were related to the respective coronary artery territories. Peak rate-pressure product during steady-state dobutamine infusion (18·493 ± 4·315 mmHg. min) was significantly lower (<0·01) than during EST (21·316 ± 4·937 mmHg. min). Dobutanine-induced wall motion abnormalities were observed in 22/26 (85%) MR studies and 20/26 (77%) patients had a pathological EST. Regional asynergy induced by dobutamine-MRI occurred in 11/15 (73%) patients with single and 11/11 (100%) with multi-vessel disease. Sensitivity and specificity for the detection of a stenosed coronary artery were 87% and 100% for the left anterior descending, 62% and 93% for the left circumflex and 78% and 88% for the right coronary artery respectively. In conclusion, dobutamine-MRI is a well tolerated, non-exercise dependent test for the detection and localization of hzaemodynamically significant coronary artery stenoses with a diagnostic accuracy similar to that previously reported for high-dose dipyridamole MRI but with a better control of stress intensity and duration. [ABSTRACT FROM PUBLISHER]

We evaluated the acute therapeutic effects of the oral administration of n (10mg) and diltiazem (120 mg) alone and in combination in 16 patients with effort angina. The 16 patients (13 men and three women; mean age 59±7 years) performed a symptom-limited bicycle exercise stress test 3 h after placebo or active substance administration. Maximal work load, exercise duration and time to 1 mm ST segment depression were significantly increased and ST depression at peak exercise was significantly decreased by the combination of drugs. N and diltiazem alone similarly improved exercise duration as markedly as their combination. One patient stopped the test after all three treatments for angina associated with ST depression > 2mm. The combination of drugs yielded the best symptomatic effect: only four patients complained of angina in comparison to eight and seven patients after diltiazem and n respectively. Nifedipine and diltiazem are effective and safe antianginal drugs. Some patients respond better to one drug than to the other. Patients who remain symptomatic in spite of maximal doses of a single drug may derive some benefit from combination therapy. [ABSTRACT FROM PUBLISHER]

The aim of this study was to evaluate the efficacy and possibly the mechanism of action of gallopamil and diltiazem in a double-blind crossover trial in patients with effort ischaemia. Twenty male patients (mean age 57±6 years) with documented coronary atherosclerosis and exercise-induced ischaemia (ST depression ≥ 0.15 mV) completed the study, which consisted offour 7 day periods. At the end of each period a multistage bicycle exercise stress test was performed under placebo (first and third periods) and randomly under gallopamil (50 mg t.i.d.) or diltiazem (90mg t.i.d.) in the second and fourth periods. Both drugs significantly increased time to ischaemia (0.15 m VST depression) as compared toplacebo, from 7.9 ± 1.7 min to 8.9 ± 1.1 min (diltiazem) and 9.1 ± 1.6 min (gallopamil) with no significant dfference between the two drugs, and reduced the maximal extent of ST shift from 0.18 ± 0.08 mV to 0.13 ± 0.04 mV (diltiazem) and0 12 ± 0.05 mV (gallopamil). Analysis of the results from the whole population showed that the beneficial effect did not appear to be related to any specific parameter. Individual analysis showed that 13/20 patients under gallopamil and 13/20 under diltiazem increased time to ischaemia, while this was unchanged or reduced in the remainder. A positive correlation between changes in time to ischaemia and changes in rate × pressure product at ischaemia was found in both those administered gallopamil (R 0.80, P <0.01) and diltiazem (R 0.65, P <0.01). Multiple regression of all considered parameters andstepwise analysis showed that changes in rate × pressure product at ischaemia were the independent variables that accounted for the longer time to ischaemia. In conclusion, both gallopamil and diltiazem at the doses used in the present study did not significantly reduce myocardial oxygen demand and were possibly effective by improving oxygen supply. [ABSTRACT FROM PUBLISHER]

The incidence and prognostic significance of silent myocardial ischaemia in 165 patients who survived a first acute myocardial infarction were assessed by means of maximal exercise stress test and 24 h continuous ECG monitoring performed before discharge. During the 1 year follow-up period 10 cardiac deaths occurred; moreover seven patients suffered a fatal myocardial re-infarction and 14 developed unstable angina. Cardiac death occurred in five of 40 patients (12.5%) with ST segment depression on stress test by in only three of 117 (2.6%) without ST segment changes (P<0.01). One-hundred-and- three of 117 patients (88.0%) without angina or ST segment depression on stress testing survived 1 year without cardiac events, compared with 24 of 40 patients (60.0%) with ST segment depression whether or not associated with angina (P < 0.001). Cardiac death occurred in five of 25 patients (20.0%) with ST segment depression on continuous ECG monitoring, compared with five of 140 (3.6%) without (P<0.01). One-hundred-and-seventeen out of 140 patients (83.6%) without angina or ST segment depression survived 1 year follow-up without cardiac events, compared with 13 of 25 (52.0%) with ST segment depression with or without angina (P<0.01). Classifying patients in a 2 × 5 contingency table according to the occurrence of ST segment depression on exercise testing and/or ECG ambulatory monitoring, the Yates corrected chi-square test showed a significant pattern when cardiac deaths and cardiac events were considered together (P < 0.01). However, in patients with exercise ST segment depression, the incidence of cardiac deaths and cardiac events was not influenced by the occurrence of ST segment changes during continuous ECG monitoring. All eight patients who stopped exercising before reaching the target heart rate because of dyspnoea (five patients), arrhythmias (two patients), or hypertension (one patient) had ST segment depression during ECG monitoring: two of them died during follow-up and three suffered from unstable angina. Thus, ST segment analysis of ambulatory ECG yields prognostic information in patients with a doubtful stress test result and is a useful technique after acute myocardial infarction. However, caution is needed when evaluating patients without ischaemia during ECG monitoring if a stress test is not available. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to evaluate the prognostic usefulness of basal electrocardiogram and exercise stress test in 374 patients with unstable angina submitted to coronary angiography during the same hospitalization period. After stabilization of symptoms by medical therapy, patients were subdivided into four groups according to the ECG and stress test: Group 1 (54 patients with normal ECG and exercise stress test negative for ischaemia); Group 2 (86 patients with normal ECG and exercise stress test positive for ischaemia); Group 3 (59 patients with abnormal ECG and exercise stress test negative for ischaemia); Group 4 (175 patients with abnormal ECG and exercise stress test positive for ischaemia). The severity of coronary atherosclerosis and impairment of left ventricular function increased progressively from Group 1 to 4, although differences in ventricular function were not significant between Groups 2 and 3. When discharged, patients were treated with verapamil and nitrates and followed for a period ranging from I to 8 years; during follow-up, only one patient of Group 1 underwent coronary bypass surgery, compared to 22, 7 and 46 patients in Groups 2, 3 and 4, respectively. The eight-year survival rate in the four groups (1–4) was 100%, 97%, 88% and 70%, respectively. Statistically significant differences were observed between Groups 1 and 3, 1 and 4, 2 and 4, and 3 and 4. Thus, the ECG and exercise stress test allow a population of patients with unstable angina to be selected (Group 1), having excellent long-term prognosis. These patients could avoid angiography, thereby reducing hospital costs, without compromising their health. [ABSTRACT FROM PUBLISHER]

Multivariate analysis has been proposed to enhance diagnostic accuracy of the exercise test in coronary artery disease. To quantify the improvement given by multivariate analysis in comparison with ST segment depression alone during exercise test, 558 men without previous myocardial infarction were studied retrospectively. All the patients underwent a symptom-limited Bruce protocol with computer-averaged recordings in v5, a VF, V2. Coronary angiography was performed within the following 90 days. Prevalence of coronary artery disease (diameter narrowing of 50%or greater) was 0.56. Among 12 clinical and exercise parameters studied by stepwise multivariate analysis, five were found to reach the maximal accuracy: (1) exercise duration, (2) history of typical angina, (3) typical angina during the test. (4) age, (5) maximal heart rate. In comparison with ST depression, multivariate analysis significantly improves accuracy (74.6 vs, 66.8%, P<0.01) by increasing sensitivity (0.68 vs. 0.59, P<0.05) without affecting specificity (0.83 vs. 0.76, NS). Thus, in a group of men without infarction and a low prevalence of coronary artery disease, multivariate analysis with five easily collected variables is more accurate than ST segment depression alone during exercise. In addition, ST depression did not appear as discriminant as exercise duration for diagnostic purposes. This finding emphasises the importance of performing a symptom-limited exercise test. [ABSTRACT FROM PUBLISHER]

A decrease in cardiac parasympathetic tone is a recognized finding in patients with ischemic heart disease, correlating closely with disease severity and overall survival. The aim of this study was to assess whether transdermal scopolamine (Tds), which increases parasympathetic tone in healthy volunteers, increases vagal tone in patients with severe CAD and whether it might have an antiischemic effect. Fifteen patients (10 men, aged 55 ± 8 years) with three-vessel CAD, but with no prior MI and preserved ventricular function, underwent 24-hour Holter monitoring and exercise testing before and after wearing a scopolamine patch for 24 hours. Time-domain measures of heart rate variability (HRV) and the total number and duration of ischemic episodes were obtained from the Holter recordings for each patient. Tds significantly (P < 0.05) increased the values of all HRV measures. Tds also reduced the total number of ischemic episodes (from 273 to 159, P < 0.05) and their total duration (from 136 to 46 min per patient, P < 0.05). Tds also increased treadmill exercise duration from 293 ± 101 to 345 ± 95 seconds (P < 0.05) and the time to 1-mm ST depression from 177 ± 105 to 244 ± 128 seconds (P < 0.02), while maximum ST depression was reduced from 2.86 ± 0.6 to 2.3 ± 0.3 (P < 0.05). No significant side effects were observed. Tds modifies the autonomic balance in patients with severe CAD toward a condition associated with a better prognosis. It may also be useful as an adjunctive treatment for ischemic heart disease. [ABSTRACT FROM AUTHOR]

Coronary artery disease is one of the most dreadful and life-threatening diseases out of all cardiac diseases. The diagnosis and management of coronary artery disease comprise stepwise approaches. All these approaches are mostly guideline-driven. While the majority of the time, guidelines help us take the most appropriate care, exceptions do exist. For example, patients may have unusual risk factors and abnormal test results; however, they do not fit into the guideline algorithm to proceed further.  This case report of a 68-year-old male patient depicts a true example of such a situation. He presented to the cardiologist's office for pre-operative cardiac evaluation for urological surgery. In view of associated risk factors, an exercise stress test was done, which showed critical abnormalities. As per the pre-operative cardiac assessment guidelines, the patient did not meet the criteria for further testing. However, a clinician's strong judgment and persistent negotiation superseded those barriers. Given critical abnormalities of the exercise stress test, the patient underwent cardiac catheterization. He was found to have triple vessel disease on cardiac catheterization. The scheduled surgery was withheld, and the patient underwent a coronary artery bypass graft. This life-threatening condition could have been easily missed if only the guidelines were to be followed. While guidelines cover a significant portion of the bell curve, this case report represents the importance of not missing the tail ends of the curve. It enhances the importance of thinking out of the box based on clinical training and expertise., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Jha et al.)

We examined whether resting levels and exercise-induced changes during exercise ECG stress test (EST) of cardiac Troponin T (cTnT), NT-proBNP and prothrombotic markers were affected by revascularization in patients with coronary artery disease (CAD).EST1 was performed before coronary angiography and revascularization, and patients (n  =  20) with confirmed CAD, performed another EST (EST2) 9 weeks later. Blood samples were drawn at rest and within five min after termination of ESTs.cTnT and NT-proBNP increased during exercise at both ESTs (p < 0.001, all). Resting cTnT levels at EST2 versus EST1 were significantly higher (p  =  0.02) whereas NT-proBNP did not differ. At both visits, increased D-dimer (p  =  0.008 and <0.001), pro-thrombin fragment 1  +  2 (p  =  0.009 and 0.001) and tissue factor pathway inhibitor (TFPI) (p < 0.001 and 0.001) during exercise were demonstrated. Resting levels of endogenous thrombin potential (ETP) and TFPI were reduced at EST2 versus EST1 (p < 0.01).Revascularization did not affect exercise-induced release of cardiac and prothrombotic biomarkers and did not reduce resting levels of cTnT or NT-proBNP, suggesting revascularization per se not to prevent secretion of biomarkers. The lower resting levels of ETP and TFPI after revascularization may however, be indicative of reduced thrombin generation and endothelial activation.Clinicaltrials.gov, CADENCE, NCT01495091 https://clinicaltrials.gov/ct2/show/NCT01495091?term = 01495091&draw = 2&rank = 1.

Exercise enables continuous glycemic control for diabetic patients, and it is effective in preventing diabetic complications and maintaining emotional stability. However, it is difficult for diabetic patients to know the appropriate intensity and duration of exercise. Excessive exercise causes sudden hypoglycemia, and patients avoid therapeutic exercise or perform it conservatively owing to the repeated hypoglycemia symptoms. In this paper, we propose a new therapeutic exercise platform that supports type 2 diabetes patients to exercise regularly according to the exercise prescription received from the hospital. The proposed platform includes the following three significant contributions. First, we develop a hardware platform that automatically tracks and records all aerobic exercise performed by a patient indoors or outdoors using a wearable band and aerobic exercise equipment. Second, we devise a patient-specific exercise stress test to know whether the patient is exercising according to his or her usual exercise regimen. Finally, we develop a mobile application that informs patients in real-time whether they are exercising appropriately for their exercise regimen each time they exercise. For platform evaluation and future improvement, we received satisfaction ratings and functional improvements through a questionnaire survey on 10 type 2 diabetes patients and 10 persons without a diabetes diagnosis who had used the proposed platform for more than 3 months. Most users were (1) satisfied with automatic exercise recording, and (2) exercise time increased. Diabetics reported that their fasting blood glucose was dropped, and they were more motivated to exercise. These results prove that exercise must be combined with medication for blood glucose management in chronic diabetic patients. The proposed platform can be helpful for patients to continue their daily exercise according to their exercise prescription. [ABSTRACT FROM AUTHOR]

Background: Pharmacologic challenge test is often used to diagnose Brugada syndrome (BrS) when spontaneous electrocardiograms (ECG) do not show type I Brugada pattern but reported sensitivity varies. The role of the exercise stress test in diagnosing Brugada syndrome is not well-established., Case Summary: A patient had a type I Brugada pattern ECG during the recovery phase of exercise stress test but had a negative procainamide challenge test. He had a loop recorder implanted and later survived a ventricular fibrillation (VF) arrest provoked by coronavirus disease 2019 (COVID-19). Electrocardiogram on arrival showed type 1 Brugada pattern. He was discharged after implantable cardioverter-defibrillator implantation. He later underwent genetic testing and was found to be heterozygous for c.844C>G (p.Arg282Gly) mutation in the SCN5A gene., Discussion: Type 1 Brugada pattern ECG may be unmasked by ST-segment augmentation during recovery from exercise. Exercise stress test may play a role in the diagnosis of Brugada syndrome when suspicion for Brugada syndrome remains after a negative procainamide challenge test or if the patient has exercise-related symptoms. COVID-19 can unmask BrS and trigger a VF cardiac arrest., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Objective: To examine the combination of heart rate recovery (HRR) and heart rate variability (HRV) in predicting atrial fibrillation (AF) progression., Methods: Data from patients with a first detected episode of AF who underwent treadmill exercise testing and 24-h Holter electrocardiography were retrospectively analysed. Autonomic dysfunction was verified using HRR values. Sympathetic and parasympathetic modulation was analysed by HRV. AF progression was defined as transition from the first detected paroxysmal episode to persistent/permanent AF., Results: Of 306 patients, mean LF/HF ratio and HRR did not differ significantly by AF progression regardless of age (< or ≥65 years). However, when the LF/HF ratio was divided into tertiles, in patients aged <65 years, the mid LF/HF (1.60-2.40) ratio was significantly associated with lower AF progression rates and longer maintenance of normal sinus rhythm. For patients aged <65 years, less metabolic equivalents were related to higher AF progression rates. For patients aged ≥65 years, a low HRR was associated with high AF progression rates., Conclusion: In relatively younger age, high physical capacity and balanced autonomic nervous system regulation are important predictors of AF progression. Evaluation of autonomic function assessed by age could predict AF progression.

Objective: To study the significance of ST-segment depression during 'recovery' compared to that 'during stress' and 'both the phases' in exercise stress test., Methods: Patients with positive exercise stress test who underwent coronary angiography (CAG) from 1st January 2017 to 31st December 2018 were studied. Patients were divided into 3 groups- Group A with ST-depression restricted to recovery phase, group B with ST-depression restricted to stress phase and group C with ST-depression seen both during exercise and recovery. All patients underwent CAG. Sensitivity, specificity, and predictive values of each of these groups in diagnosis of significant coronary artery disease (CAD) were analysed and compared., Results: Total 300 patients were studied. Mean age of the study population was 48.77 ± 7.94 years. 78.3% of patients with positive exercise stress test had significant CAD. 96% of patients in group A had significant CAD, which was higher than in group B (88.9%) & group C (70.1%). The specificity, positive predictive value and negative predictive value of ST-segment depression in group A (96.92%, 96% and 25.2% respectively) were higher than that of ST-depression in group B (89.23%, 88.89% and 24.47% respectively) and group C (13.85%, 70.05% and 7.96% respectively). Sensitivity and accuracy of ST-depression in group A were lower (20.43% and 37% respectively), compared to other 2 groups., Conclusion: Patient with ST-depression restricted to recovery phase had highest specificity, positive predictive value, and negative predictive value. However, accuracy was highest in group with both stress phase and exercise ST-segment depression., Competing Interests: Declaration of competing interest All author has none to declare., (Copyright © 2021 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Background: Abnormal left ventricular systolic and diastolic function and reduced exercise capacity are associated with worse prognosis following ST-elevation myocardial infarction (STEMI). However, evidence is lacking on the determinants of exercise capacity following STEMI. We sought to determine the impact of systolic and diastolic dysfunction on exercise capacity and outcomes following first-ever STEMI., Methods: In a retrospective analysis of 139 consecutive STEMI patients who had a transthoracic echocardiogram following STEMI and completed exercise treadmill testing, the primary outcome was to identify clinical and echocardiographic determinants of exercise capacity, and the secondary outcome was to identify determinants of major adverse cardiac events (MACEs)., Results: Mean number of metabolic equivalents (METs > 8) was used as a cut-off. Age, female sex, anterior infarction, abnormal diastolic function, minimum left atrial indexed volume (LAVI min ) ≥ 18 mL/m 2 , average e', and E/e' were associated with METs ≤ 8, but not left ventricular ejection fraction (LVEF). On multivariate analysis, LAVI min (OR 4.3, 95%CI 1.3-14.2; p = 0.017), anterior infarction (OR 2.6, 95%CI 1.2-5.9; p = 0.022), and abnormal diastolic function (OR 3.73, 95%CI 1.7-8.4; p = 0.001) were independent predictors of METs ≤ 8. On Kaplan-Meier analysis, METs ≤ 8 ( p = 0.01) and abnormal diastolic function ( p = 0.04) were associated with MACEs (median follow-up 2.3 years). METs ≤ 8 was an independent predictor of MACEs (HR 3.4, 95%CI 1.2-9.8; p = 0.02)., Conclusions: Following first-ever STEMI, increased LAVI min , anterior infarction, and abnormal diastolic function were independent predictors of reduced exercise capacity. Furthermore, reduced exercise capacity was an independent predictor of MACEs. These results highlight important prognostic and therapeutic implications related to abnormal diastolic function in STEMI patients that are distinct from those with LV systolic impairment.

Background: Left atrial (LA) strain and dysfunction are early markers of diastolic dysfunction, associated with poor exercise capacity in adults with hypertrophic cardiomyopathy (HCM). Literature on assessment of LA mechanics in pediatric HCM is lacking. The aim of this study was to assess LA strain and LA function in pediatric patients who have HCM with (phenotype positive [P+]) and without (genotype positive, phenotype negative [G+P-]) ventricular hypertrophy and evaluate their correlation with exercise stress test parameters., Methods: Seventy-eight children (3-25 years of age) with HCM (P+, n = 46; G+P-, n = 32) and 20 healthy control subjects were retrospectively studied. LA conduit function, reservoir function, and pump function were computed using phasic LA volumetric analysis. LA reservoir strain (LASr) and LA contractile strain were measured using speckle-tracking echocardiography. Exercise test findings within 12 months of echocardiography were recorded., Results: LA conduit function (36% vs 48%, P < .001) and LA reservoir function (137% vs 180%, P < .001) were lower in P+ than in G+P- patients. LA contractile function did not differ between the groups (31% vs 32%, P = .87). Compared with patients with G+P- HCM, those with P+HCM had lower four-chamber LASr (29% vs 41%, P < .001), two-chamber LASr (30% vs 41%, P < .001), average LASr (29% vs 42%, P < .001), and LA contractile strain (9% vs 12%, P = .016). In the cohort of patients with HCM who underwent stress testing (n = 35), LA conduit function weakly correlated with aerobic capacity (r = 0.42, P = .019)., Conclusions: Children with P+HCM have reduced LA function, measurable by both volumetric and strain analysis. Altered LA mechanics are associated with poor exercise capacity. This study lays the foundation for the evaluation of novel LA parameters in pediatric HCM and warrants larger longitudinal studies to assess its clinical significance., (Copyright © 2021 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Abstract: The phenomenon of cumulative exercise-induced left ventricular function impairment was studied in 40 patients with non-obstructive hypertrophic cardiomyopathy with resting normal left ventricular function and no increase in ejection fraction on exercise. All patients underwent two symptom-limited exercise tests one-hour apart. Cumulative myocardial dysfunction was seen in 13 patients (group I) but not in the remaining 27 patients (group II). During follow-up, group I showed more commonly than group II a deterioration in symptoms (67% vs 22%, P =0.025) and left ventricular function (50% vs 9%, P =0.019). In conclusion, cumulative exercise-induced myocardial dysfunction can occur in hypertrophic cardiomyopathy and may be associated with clinical deterioration and worse outcome. [Copyright &y& Elsevier]

We describe the clinical and genetic characteristics of the family, in which the diagnosis of LQT1 had been made. The electrocardiogram (ECG) characteristics of this patient indicated the likelihood of LQTS1. Polymorphic ventricular extrasystolies and episodes of polymorphic non-sustained ventricular tachycardia were confirmed by Holter ECG monitoring. On the exertional electrocardiogram polymorphic ventricular tachycardia (torsade de pointes) was recorded. Direct sequencing of both DNA strands revealed the absence of mutations or polymorphisms in the KCNQ1, HERG, and SCN5A genes. [ABSTRACT FROM AUTHOR]

Controversy surrounds whether to define resting diastolic blood pressure (DBP) as the onset of the fourth or fifth Korotkoff phase (K4, sound muffling, or K5, sound disappearance) in children and adolescents. Although undetectable in some children (due to sounds continuing to zero cuff pressure), K5 is currently recommended for consistency with adult practice and because K4 can be difficult to discern or undetectable. However, to our knowledge, no studies have specifically assessed the reliability of measuring DBP with K4 and K5 in children and adolescents under exercise conditions. We therefore measured DBP before and immediately after a Bruce protocol stress test in 90 children and adolescents aged 12.3 ± 3.5 years (mean ± SD) in a cardiology clinic setting. When detected, K4 and K5 were 63.5 ± 9.2 and 60.2 ± 12.6 mmHg, respectively, at rest and 59.2 ± 14.6 mmHg (p = 0.028 vs rest) and 52.9 ± 18.3 mmHg (p < 0.001), respectively, immediately post-exercise. K4 and K5 were not detected in 41% and 4% of participants at rest or in 29% and 37% post-exercise, respectively, while K5 resulted in unrealistic DBP values (<30 mmHg) in an additional 11%. Better exercise performance was associated with a more frequent absence of K5 post-exercise, and after excluding participants performing at <10th percentile for age, post-exercise K4 was absent in 23%, and plausible K5 values were not obtained in 59% (p < 0.001). Although neither K4 nor K5 alone were reliable measures of DBP immediately post-exercise, a novel hybrid approach using K4, if detected, or K5, if not, produced reasonable DBP measurements in 97% of participants., (© 2021. The Author(s), under exclusive licence to The Japanese Society of Hypertension.)