Oxygen Uptake, Heart Rate and Oxygen Pulse at Maximal Exercise / 대한내과학회지

OBJECTIVES: Despite the fact that determinations of cadiorespiratory fitness levels by exercise stress tests are becoming widely used in healthy individuals as well as in patients with cardiopulmonary diseases, the normal standards in this field have not been well established in Korea. The purpose of this study is to provide normal standards or reference values for the VO2 max, HR max and O2 pulse max for normal Korean adults by age and sex, along with the derivation of regression formulae of these parameters. METHODS: In 1,000 healthy adults (20-66years) consisting of 603men and 397women, symptomlimited maximal exercise was carried out by Bruce protocol, allowing holding on to the hand rail of the treadmill during exercise for the safety purpose. All the subjects were non-athletes and were members of a health center and were more conscious about their health and physical fitness than the ordinary population. RESULTS: The VO2 max and HR max were decreased with age as expected and, as a whole, the values of the VO2 max and HR max of females were approximately 84% and 90% of those of males, respectively. Estimated yearly reductions in the V max for males and females were 0.45 and 0.32mL/kg/min, respectively and those of the HR max were 0.72 and 0.76/min, respectively. The O2 pulse max of the female was approximately 70% of that of the male, and was slightly related to weight and exercise time. The regression equations of the parameters obtained using exercise time (ET, sec), age (A, year), weight (W, kg) and sex (S, O=male; 1= female) were: HR max=215.3-0.74A-5,04S, O2 pulse max= 5.371+0.216W+0.0107ET-1.505S and VO2 max=40.612+1.950ET-0.206A-0.147W-6.060S, CONCLUSION: The VO2 max in our study was higher than hitherto reported. This was primarily due to longer exercise time of the subjects on the treadmill, because they were allowed to hold on to the hand rail during exercise. And also, the fact that our subjects, being members of a health center, might have had higher physical fitness levels than general population could have contributed to the high VO2 max. Thus, we feel that our results could be the ideal target or- reference values to be achieved for those patients or individuals who have to do the tests with holding on to the rail of a treadmill for safety purpose.

Respiratory Compensation Thresholds in Healthy Korean Adults / 대한내과학회지

OBJECTIVES: The respiratory compensation threshold(RCT) is thought to be one of parameters by some for the evaluation of physical performance despite its controversial status. The purpose of this investigation is to establish the reference values of the RCT in healthy Korean adults, and to examine the usefulness of this parameter in evaluating physical performance. METHODS: Symptom-limited maximal exercise test by Bruce protocol was carried out, and RCT and AT were determined by the aid of the computerized V-slope method, along with the VO2 max, in 441 healthy Korean adults consisting of 284 men and 157 women aged from 20`s to 60`s. In addition, correlation between RCT and AT was observed, and regression equations of the RCT were also derived. RESULTS: The RCT VO2 was tended to decrease with age in men, but not in women and the RCT VO2 of women was 26-30% less than that of men. The ratio of RCT VO2 to VO2 max (RCT VO2/VO2 max) was tended to increase with age and the RCT V was significantly correlated with AT VC4 and VO2 max in both sexes. CONCLUSION: Our study reveals that the RCT is another useful submaximal index along with the AT in evaluating physical performance. The regression equation of the RCT was RCT VO2(L/min)=1.4232-0.0102 A(age in year)+0.0204 W(weight in kg)-0.4889 S (sex, coded O for males and 1 for females).

Cardiopulmonary Response to Maximal Exercise Loading in Professional Soccer Players

BACKGROUND: Although maximal exercise stress tests are widely used in the athletic and medical fields, studies on professional soccer players are few. The purpose of our study is to observe the cardiopulmonary response to maximal exercise loading and the AT in professional soccer players. METHODS: Maximal exercise stress tests were carried out by a ramp protocol using a treadmill on 20 professional soccer players with a mean age of 25.2 years and with over 10 career years. The tests were also done on 21 college students majoring in physical education with a mean age of 19.4 years, which served as the control group. The AT was determined by the V-slope method. RESULTS: In the players, the VO2 max, VCO2 max and O2 pulse max were significantly larger than those in the control group, and the HR max was smaller for their ages. The VE max, VT max and RP max showed not much difference between the 2 groups but the VE max/VO2 max and VE max/VCO2 max were significantly lower in the players. The AT was larger in the players but the AT/VO2 max was essentially similar to that of the control group. CONCLUSION: Our study reveals that the professonal soccer players, despite their mean ages were approximately 6 years older than the subjects in the control group, had larger VO2 max and VCO2 max, and smaller HR max for their ages. The VE max was similar in both groups. This suggests that the players have higher aerobic capacity than the control group and exchange respiratiory gases more efficiently.

Cardiorespiratory Responses of Pilots to Maximal Exercise Loading

BACKGROUND: To provide some fundamental physiological basis for the physical training of pilots to improve orthostatic intolerance, cardiorespiratory responses to the symptom-limited maximal exercise loading were studied in pilots and non-pilots, and the results were compared. METHOD: Cardiorespiratory reponses to the symptom-limited maximal exercise loading by Bruce protocol was studied in 11 pilots and 11 matched controls (non-pilots). RESULTS: Comparisons of various data at maximal exercise in the pilots with those in the controls revealed that RR, VE/M2, VE/VO2, VE/VCO2, VT/VC and VE/MVV as well as HR, VO2, O2 pulse and AT showed no significant difference. CONCLUSION: The fact that the aerobic power in the pilots is not superior to that in the controls seems to emphasisze the necessity of aerobic endurance training along with muscular strength training to improve orthostatic tolerance of pilots flying modern high-performance aircrafts.

Cardiorespiratory response to maximal exercise loading in mild anemia

BACKGROUND: Mild iron deficiency anemia is known to be asymptomatic in most of the cases. In view of this, we studied response of the mild anemics to the maximal exercise loading test to learn whether or not they respond similarly to the normals. METHODS: The maximal exercise loading tests by Bruce's protocol were carried out in 22 female asymptomatic anemics with hemoglobin level of between 10.0gm/dL and less than 12.0gm/dL, and the results were compared with those of 44 non-anemic matched controls with mean hemoglobin level of 13.1gm/dL. The ages in both groups were in their 30's to 40's, and even the anemics were otherwise normal clinically and on various laboratory tests. RESULTS: There were no significant difference between two groups in VO2 max, HR max, VCO2 max and VE max and their derivatives including VT/VC and VE/MVV. CONCLUSIONS: Our results indicate that in patients with mild iron deficiency anemia, the cardiorespiratory response to maximal exercise loading is not different from the normals, and suggest that oxygen transport to tissues is not affected even at maximal exercise. probably by adaptive compensatory mechanism.

Comparisons of Electrocardiograms and Echocardiograms in Soccer Players before and after Intensive Training

BACKGROUND: In athlete's heart, functional and structural alteration are main features. We studied electrocardiograms(ECG's) and echocardiograms(UCG's) in soccer players before and after intensive training. METHODS: Fifteen soccer players with the mean age and career of 19.3 and 8.5 years,respectively,underwent intensive training for 5-5.5 months, which included running of 2 km daily during the last 2-2.5 months. Comparisons of ECG's and UCG's recorded before and after the training were made. RESULTS: The major abnormal finding in pre-training ECG's was high voltage being seen in 40% of the cases, and in UCG's left ventricular(LV) dilatation and/or hypertrophy or asymmetrical septal hypertrophy(ASH) were noted in approximately 80% of the cases. The incidences of these finding after the intensive training were essentially unchanged, and the mean of pre-and post-training fractional shortening(FS) and LV and left atrial dimensions were similar. The high voltage in ECG's showed no close correlation with LV dilatation or hypertrophy on UCG's. After the training, however, the mean values of the thickness of LV posterior wall and ventricular septum along with LV mass were significantly increased, and the right ventricular dimension was significantly decreased. CONCLUSIONS: The most frequent finding in ECG's and UCG's in soccer players, before and after intensive training,were high voltage, LV dilatation and /or hyperophy with or without ASH. The intensive training of 5-5.5 months duration caused no change in F8,but caused significant increase in the thickness of LV posterior wall and ventricular septum, and LV mass.

Effects of Intensive Training on Cardiorespiratory Response to Maximal Exercise Loading in Soccer Players

BACKGROUND: In order to investigate the effects of intensive training on cardiorespiratory response to maximal exercise in soccer players, graded excercise stress tests were carried out before and after the training, and the results were compared. METHODS: Fourteen male soccer players of a university team with the mean age and career of 19.9 and 7.8 years, respectively, underwent intensive training for approximately 20 weeks, 6 days a week and 4 hours a day, which included running of 2 km daily during the last 8-9 weeks. The symptom-limited maximal exercise test was done by Bruce protocol. RESULTS: After the training. HR max showed no significant changes but Vo2 max, O2 pulse and AT were increased approximately 13%, 12% and 10%, respectively. At maximal exercise, the V(E)/M2 was also increased 18%, but VE/MVV was significantly decreased owing to a marked increase in MVV. However, the rest of various ventilatory parameters showed no significant changes. CONCLUSION: These data indicate that the intensive training of about 20 weeks duration can further improve the level of cardiorespiratory fitness in the soccer players who have been regularly trained and are already highly fit.

Comparisions of Electrocardiograms and Echocardiograms in Volleyball Players before and after Intensive Training

BACKGROUND: We attempted to study functional and structural changes in the hearts of volleyball players and cardiac effects of a short-term intensive training as disclosed by electrocardiograms(ECG's) and echocardiograms(UCG's). METHODS: In 12 volleyball players of a university team with the mean age and career of 19.9 and 9.2 years, respectively, comparisons of ECG's and UCG's M-mode & Doppler, were made before and after an intensive training of 8 weeks duration. The players have been trained 2-3 hours daily almost year around for many years, and the intensive and comprehensive training given for the current study was 3 hours daily, which included strenuous interval training of 20-30 minutes. The training was divided into two successive sessions. For the first session, the players ran 4km daily as a part of the training for 2 weeks. The second session included repetition of runnging at their maximal speed with short intermissions of stationary running for 6 weekes. RESULTS: The major findings in ECG's were sinus bradycardia(25.0%) and high voltage(33.3%), and those in M-mode UCG's were left ventricular(LV) hypertrophy, LV dilatation or left atrial dilatation being seen in all cases, alone or in combinations. After the training however, there were no significant changes in the incidences of these abnormal findings in ECG's & UCG's, and also in the mean of various echocardiographic parameters reflecting cardiac functions. The E and A waves in Doppler UCG's also showed no changes. The slight but significant changes after the training were limited to the increases in the mean of the sum of S wave in V1 & R wave in V5, and left atrial dimensions. CONCLUSION: In volleyball players who have been regularly trained for many years, the major findings in ECG's were sinus bradycardia and high voltage. Those in UCG's were LV hypertrophy. LV dilatation or left atrial dilation being seen in all cases, alone or in combinations. Nonetheless, after the intensive training of 8 weeks duration, the incidences of these abnormal findings in ECG's and UCG's remained essentially similar, and slight but significant changes were limited to the increases in the sum of S wave in V1 & R wave in V5, and left atrial internal dimensions. These facts suggest that in the regularly trained volleyball players, a short-term intensive training induces only limited cardiac changes as disclosed by ECG's and UCG's.

Effect of intensive training on ventilatory functions in soccer players / 결핵

No abstract available.

Echocardiographic Evaluation of Cardiac Alteration in Hypertension

The cardiac dimensions and functions were studied by analyzing simultaneously recorded M-mode echocardiograms and phonocardiograms in 24 cases of essential hypertension with no evidence of heart faliure, and also in 20 healthy adults for comparison. Thirteen hypertensives out of 24 had findings consistent with left ventricular hypertrophy on either routine chest roentgenograms or electrocardiograms or both(group II) and the remaining 11 had no such findings(group I). The posterior wall and septal thickness, and isovolumic relaxation time were significantly was increased even in the group I as well as in the group II. The isovolumic relaxation time was correlated well with the septal thickness in both groups. In contrast, a significant increase in left atrial and left ventricular systolic dimensions was noted only in the group II, and so was a significant reduction in the fractional shortening and mean velocity of circumferential fiber shortening. These findings suggest that the echocardiographic examination is useful in patients with essestial hypertension for the early dagnosis of the increased thickness of the posterior wall and the septum, and the abnormality during early diastolic relaxation of the left ventricle, prior to the appearance of the ventricular hypertrophy on the routine chest films amd/or electrocardiograms, and also that echocardiograms enable early detection of the systolic dysfunction of the hypertrophied left ventricle in the absence of apparent failure.

Ventilatory Dynamics in Hypertensive Heart Disease

Small and large airways functions were studied in patients with hypertensive heart disease in slightly ro moderately compromised state functionally. In this study, the forced vital capacity and various flow paramaeters reflecting expiratory flow rate were determined from simultaneously recorded forced expiratory volume and maximal expiretory flow volume curves in 86 cases. The closing volume was measured by a single breath nitrogen mrthod in 57 cases and airway resistance with its related parameters by a body plethysmograph in 11 cases. These results were compared with those obtained from the same numbers of healthy controls matched for sex, age and height. In the patient group, the forced vital capadity and all the observed values of flow parameters, execpt for the ratio of the first second vital capacity to the forced vital capacity, were significantly reduced than those in the controls. When the remainder of flow parameters was volume-adjusted to the forced vital capacity, however, the mean of the peak expiratory flow rate and the maximal expiratory flow rate at the 75 percent of the vital capacity were not significantly different from that of controls. In contrast, the volume-adjusted values of maximal expiratory flow were remained significantly smaller than those in the controls. The closing volume and its ratio to the vital capacity were significantly larger in the patient group. Airway resistance and its related parameters revealed no significant differences between two groups. These findings suggest that the patients with hypertensive heart disease in a mild to moderate failure are associated with restrictive ventilatory impairment and a small airways obstruction, but with little or no large airway dysfunction.

Comparison of ECG Findings between Hypertrophic Obstructive Cardiomyopathy and Hypertension with Disproportionate Septal Thickening

Electrocardiographic findings in 18 cases of hypertrophic obstructive cardiomyopathy(HOCM) were compared with those in 20 hypertensives with disproportinate septal hypertrophy(DSH) and in 20 normal controls. In conventional 12 leads electrocardiograms, abmormal Q waves were seen only in 6 cases of HOCM and none in the remadinder. The R waves were tallest in leads V4 in 6 cases(33%) of HOCM, 3(15%) hypertensives with DSH, and 4(20%) of the controls. The correlations of the QRS voltages with echocardiographically measured left ventricular dimension, interventricular septal thickness and left ventricular mass were significant in the hypertensives with DST and normal controls, but insignificant in patients with HOCM. We conclude that these electrocardiographic differences in patients with HOCM from the others would be caused by uneven distribution of hypertrophied muscle mass in the left ventricule and/or by the altered depolarization in hypertrophied cardiac muscles.

Lung Volumes and Alveolorespiratory Function in Mitral Stenosis

Lung Volumes and alveolorespiratory function were studied in 30 cases of pure or predominat mitral stenosis in slightly to moderately compromized state, and the results were compared with those in the normal controls. In patients with mitral stenosis, there was a singnificant reduction in the vital capcity and the total lung capacity, whereas the residual volume and its ratio to the total lung capacity were significantly increased. The distribution of inspired gas was uneven as reflected by increase in the lung clearnace index and in the slope of phase III of the single breath nitrogen washout curve. The alvelolar arterial oxygen tension gradient and the physiological dead space were singinificantly increased despite a singinificant decrease in the arterial carbon dioxide tension. The diffusing capacity was also reduced in some cases.

Cor Pulmonale with Particular Reference to Chronic Obstructive Pulmonary Disease and Pulmonary Tuberculosis

No abstract available.

Echocardiographic Analysis of Systolic Mitral Valve Motion in Healthy Young Males: With Particular Reference to Mitral Valve Prolapse

M-mode echocardiograms were recorded in 268 apparently healthy young male adults and the mitral valve motion during systole was analyzed. In 149 cases( 55.6%) out of 268 the predominant echo of mitral valve closure(CD line) was recorded as smooth line moving slowly anteriorly, in 48 cases(17.9%) the CD line showed an abrupt transient posterior motion during early systole, in 24 cases(9.0%) there were multiple additional echoes posterior to the CD line, 17 cases(6.3%) the mitral valve closure was recorded as pansystolic anteriorly concave echo deviating less than 2 mm from a drawn CD line, and 10 cases(3.7%) as curvilinear and anteriorly convex echo deviating from a drawn CD line. In the remaining 20 cases(7.5%), the mitral valve closure was recorded as pansystolic anteriorly concave echo deviating more than 2 mm from a drawn CD line, which was categorized to have mitral valve prolapse in the current study. However, there were no significant differneces in various echocardiographic dimensions of the heart and the aorta between those with and without mitral valve prolapse.

Differences in Systolic Time Intervals Attributable to the Type of Mechanocardiographs

Differences in systolic time intervals(STI's) attributable to the types of mechanocardiographs used for their determinations were studied in a total of 341 healthy adult males. The STI's were measured from mechanocardiograms consisting of simultaneously rocorded electrocardiograms, phonocardiograms and carotid arterial pulse tracings obtained by each of three different types of mechanocardiographs in 125, 56 and 160 subjects, respectively. The study revealed that there were slight to considerabe differences among the three groups in the correlation coefficients between the individual STI's and heart rate. Thus, regression equations using heart rate as variables, for those STI's which were significantly correlated with heart rate, differed slightly to considerably among these groups. In addition, the mean values of those STI's and their derivatives, which showed no significant correlation with heart rate, were also silghtly or significantly different among the three groups. These findings suggest that if STI's obtained from patients are to be adequately evaluated at all, each laboratory must define its own normal standards worked out by using its own methods of recording and analysis of the mechanocardiogram, and cannot rely on those proposed by others.

Antihypertensive Effect of Trimazosin in Essential Hypertension

The antihypertensive effect of trimazosin was studied in 24 cases of essential hypertension, which include 9 cases with pretreatment diastolic pressure of 114mmHg or more, for a period of 4 weeks. The average pretreatment systolic and diastolic blood pressures were approximately 175mmHg and 114mmHg, respectively. The treatment was started with 100mg of trimazosin daily in 2 divided doses and and the drug was titrated upward at weekly interval by 100mg up to 400mg/day depending on the response of the blood pressures. Routine blood counts, urinalyses, liver and kidney function tests, electrolyte balance, total serum cholesterol and triglyceride were determined before and at the end of treatment. The diastolic blood pressure fell 10mmHg or more in 20 out of 24 cases(83.3%), and in 12 cases out of 20 favorable responders it fell to 90mmHg or below. The pretreatment diastolic blood pressure in 4 nonresponders was all 115mmHg or more. The antihypertensive effect appeared during the first week of therapy and progressively increased until the end of treatment week without causing postural hypotension. Unpleasant symptoms appeared in 12 cases during treatment, which include dizziness, headache, numbness in the extremities and tinnitus in the decreasing order of frequency. However, these symptoms were mild and transient in all cases disappearing spontaneously despite continued medication. No significant biochemical changes in the blood were recorded after treatment. We conclude that trimzosin seems to be a safe and effective antihypertensive drug particularly useful for the treatment of mild to moderate hypertension.

Effects of Thoracentesis on Thoracic Impedance and Cardiac Performance

Effects of thoracentesis on thoracic impedance and cardiac performance were studied in patients with uncomplicated unilateral tuberculous pleural effusion. The speed of the removal of the pleural effusion in thoracentesis was essentially similar to that of a generally used for therapeutic purpose in daily practice. Thoracic impedance was measured in 23 cases before, 4 and 10 minutes after thoracentesis to the amount of pleural effusion aspirated was observed. In 11 cases out of 23, the changes in cardiac performance as assessed by stroke volume, cardiac output, heart rate, heather index and ratio of pre-ejection period to left ventricular ejection time(PEP/LVET) were observed 4 minutes after 150 ml to 1,000 ml of thoracentesis. In these cases, stroke volume, cardiac output, and Heather index were determined from impedance cardiograms, and PEP/LVET from mechanocardiograms recorded simultaneously with the former. A significant increase in thoracic impedance was observed both 4 and 10 minutes after thoracentesis. There was a slight but a significant correlation between the changes in thoracic impedance and the amount of pleural fluid aspirated only 4 minutes after thoracentesis. Thoracentesis showed no consistent influence on cardiac performance as reflected to stroke volume, cardiac output, heart rate, heart index and PEP/LVET. These facts suggest that measurement of thoracic impedance may be a useful method reflecting alterations in pleural fluid volumes, particularly when it occurs in a relatively short period of time, and the effects of thoracentesis of less than one liter on the cardiac functions as determined by the above-mentioned parameters were variable.

Echocardiographic Observation in Patients with Mitral Valve Prolapse

Twenty-one cases of mitral valve prolapse (MVP) diagnosed by M-mode echocardiograms were studied in regard to the underlying or associated conditions, types of MVP, and dimensions of the cardiac structures and parameters reflecting cardiac performance determined by echocardiograms. In 9 cases, MVP was thought to be idiopathic origin. Associated conditions in the remainder were 5 cases of congenital heart disease, 2 cases of rheumatic myocarditis, 1 case each of aortic valve disease, ischemic heart disease and hyperthyroidism, and 2 cases of undiagnosed cardiac conditions. There were 2 cases of buckling type of MVP and in the remainder hammock type. In these 2 patients with hammock type of MVP, mitral valve echoes were seen in the left atrium during systole in 1 case, and diastolic anterior displacement of posterior mitral leaflet in the other. In 9 cases of idiopathic MVP, cardiac dimensions and parameters reflecting cardiac performance as determined from echocardiograms showed no significant differences from those of 27 normal controls.

Effect of Diltiazem Hydrochloride on Ischemic Heart Disease: With Special Reference to the Effect on Angina Pectoris

Effect of diltiazem hydrochloride on cardiac performance with particular reference to the antianginal action was studied in 17 patients with ischemic heart disease, including 12 cases of effort angina, by means of clinical and mechanocardiographic evaluations. All patients were kept on the same medications from at least 2 weeks prior to diltiazem administration until the end of the study, and were prescribed no other antianginal drugs except for liberal use of sublingual nitroglycerin. Diltiazem was given 90mg a day in three divided doses for two weeks. Clinical and mechanocardiographic evaluations, including calculations of pressure rate product(PRP), triple product(TP) and tension time index(TTI), were made before and at a weekly interval after diltiazem administration. After the medication, heart rate, blood pressure and the pre-ejection period(PEP) with its ratio to the ejection time tended to decrease, and the decreases in heart rate and the PEP at the end of two weeks were significant. The PRP, TP and TTI were also significantly decreased at the end of the second week, and the decrease in the TTI was significant even a week after the medication. An antianginal effect, which appeared within few days, was excellent to good in over 90 percent of the cases. These facts suggest that diltiazem hydrochloride has no negative inotropic action and its antianginal effecti in its early stage of the drug administration is primarily due to coronary vasodilation and, as the drug is continued, is contributed to possibly by the decrease in the myocardial oxygen consumption as well.