Strain rate imaging by ultrasonography in the diagnosis of coronary artery disease.

Regional strain rate in the left ventricle can be assessed in real time and color mapped. The method is termed strain rate imaging (SRI), and findings correspond well with 2-dimensional echocardiography. This study addresses SRI as a method for localizing coronary lesions, compared with standard echocardiography. Twenty patients with acute myocardial infarction who underwent coronary angiography for clinical reasons were examined with SRI and standard echocardiography. Wall motion was graded by SRI color and separately by wall thickening. Strain rate imaging and 2-dimensional echocardiography results agreed well. An infarct-related artery was identified from angiograms combined with electrocardiograms. Both methods identified an infarct-related artery in 19 possible cases and had equal sensitivity and specificity for wall segments affected by lesion. Combining the information from both methods did not change accuracy. The study validates SRI as a method for assessing regional wall function in coronary artery disease. The advantages of SRI are discussed and measurements of strain rates are given.

The value of ultrasonography in predicting autoimmune thyroid disease.

Ultrasonography (US) may demonstrate a diffuse reduction in thyroid echogenicity (low-amplitude echoes) in autoimmune thyroid disease (AITD), which includes chronic lymphocytic thyroiditis and Graves' disease, as well as in subacute thyroiditis. The reported occurrence of this finding in AITD varies from 19% to 95%. To assess the validity of diffuse reduction in thyroid echogenicity as a predictor of AITD, 3,077 patients referred for US of the thyroid were examined prospectively with regard to reduced versus normal thyroid echogenicity. The most frequent reasons for referral were goiter, thyroid dysfunction, neck discomfort, and/or difficulty in swallowing. Ultrasonography demonstrated diffuse reduction in thyroid echogenicity in 485 patients. Of these, 452 patients had available records of fine-needle aspiration biopsy (FNAB), and were included in the study. From the remaining patients, with normal thyroid echogenicity, 100 consecutive patients were selected as controls. In 411 of the 452 study patients (90.9%) there was at least one laboratory finding consistent with possible AITD: cytology indicating lymphocytic thyroiditis, 287 of 363 patients (79.1%) with diagnostic specimens; elevated levels of peroxidase antibodies (TPOAb), 225 of 337 (66.8%); elevated thyrotropin (TSH) levels, 290 of 450 (64.4%); or low TSH levels, 79 of 450 (17.6%). The final diagnosis was: chronic autoimmune (Hashimoto's) thyroiditis in 352 patients; Graves' disease in 47 patients; subacute (granulomatous) thyroiditis in 7 patients; toxic nodular goiter in 3 patients; and toxic adenoma in 2 patients. In the remaining 41 patients, those without laboratory results consistent with AITD, the final diagnosis was colloid goiter in 37 and thyroid cancer in 4 patients. In the 100 controls, laboratory results were consistent with possible AITD in 14 patients: elevated TPOAb levels in 5 of 49 patients with retrieved antibody results; lymphocytic thyroiditis in 2 patients; elevated TSH levels in 2 patients; and low TSH levels in 2 patients. In these controls, the final diagnosis was: chronic autoimmune thyroiditis in 7; toxic nodular goiter in 6 patients, and toxic adenoma in 1 patient. The corresponding positive and negative predictive values of reduced thyroid echogenicity as an indicator of AITD were 399 of 452 (88.3% [95% CI, 85% to 91%]), and 93 of 100 (93.0% [95% CI, 88% to 98%]), respectively. Thus, diffuse reduction in thyroid echogenicity was a valid predictor of AITD.

[Myocardial infarction in young patients. Consequences of routine coronary angiography]. / Hjarteinfarkt hos unge pasientar. Konsekvens av koronar angiografi brukt som rutine.

The value of coronary angiography in unselected patients after myocardial infarction is still controversial. Our study includes 131 consecutive young patients (< 50 years old) in whom coronary angiography was performed after their first myocardial infarction. Angina pectoris was present in 71 (54%), and silent ischemia in 11 (9%): 49 patients (37%) were asymptomatic and without myocardial ischemia. Significant coronary artery stenosis was present in 119 patients (91%). A larger share of the patients with angina or silent ischemia than of those without had multivessel disease and high angiographic risk, and more of them were referred for revascularization. However, many of the asymptomatic patients with a negative result on the exercise test also had serious, high risk coronary heart disease, and needed revascularization. Thus, although the presence of angina or myocardial ischemia can identify a group of patients with serious coronary heart disease, the diagnostic precision is low, and if coronary angiography is not performed, many young patients with high risk disease may be overlooked.

[Regional differences in the use of coronary angiography in the examination of heart patients]. / Regionale forskjeller i bruk av koronar angiografi for utredning av hjertepasienter.

We monitored, for a period of 26 months, the use of coronary angiography at a catheterisation laboratory serving a Norwegian county with two distinct geographical regions, each with one referring hospital. Catheterisation was used twice as often in the one region as in the other. The patients from both regions belonged to the same angina function class at referral, and there was no significant difference in the findings at angiography or the need for coronary angioplasty and coronary artery bypass grafting. The incidence of coronary artery disease and the availability of coronary angiography was also the same in the two regions. The main reasons for the different rates of use are a more liberal referral policy in the high rate region, and less access to specialists in the low rate region.

[Cardiac natriuretic peptides as markers of left ventricular dysfunction]. / Kardiale natriuretiske peptider som markør for venstre ventrikkel-dysfunksjon.

The objective of this study was to critically evaluate the usefulness of atrial natriuretic factor (ANF), the N-terminal fragment of the ANF pro-hormone (pro-ANF) and B-type (brain) natriuretic peptide (BNP) determination as screening tests for identifying patients with mild left ventricular (LV) impairment. The sample consisted of a consecutive series of 254 patients undergoing diagnostic left-sided cardiac catheterization. Logistic regression analysis showed that plasma BNP was the best predictor of increased LV end-diastolic pressure, decreased LV ejection fraction and LV dysfunction (LV ejection fraction < or = 45% and LV end-diastolic pressure > or = 15 mm Hg). For the detection of LV dysfunction the areas under the receiver-operating characteristic function, an index of overall diagnostic accuracy, were 0.789 for BNP, 0.665 for ANF and 0.610 for pro-ANF. In conclusion, plasma BNP appears to be a better indicator of LV function than plasma ANF or pro-ANF. However, the overall diagnostic value of circulating ANF, pro-ANF, and BNP as indicators of mild LV dysfunction is relatively modest.

Cardiovascular and electrocardiographic effects of iopentol in left ventricular angiography. Comparison of the low-osmolar, non-ionic iopentol (Imagopaque 350) and the hyper-osmolar, ionic metrizoate meglumine-Na-Ca (Isopaque Coronar 370) in patients with coronary heart disease.

UNLABELLED: The aim of the study was to evaluate and compare the hemodynamic and electrocardiographic effects following injection of the non-ionic, low-osmolar contrast medium iopentol (Imagopaque 350, Nycomed Imaging AS, Oslo, Norway) and the ionic, hyper-osmolar contrast medium metrizoate meglumine-Na-Ca (Isopaque Coronar 370, Nycomed Imaging AS, Oslo, Norway) when used for left ventricular angiography. The study was performed in a double-blind, randomized manner in 82 patients with severe coronary heart disease. The patients who received iopentol experienced less adverse events and subjective discomfort of lesser intensity than those who received metrizoate (p = 0.0001). Both contrast media induced a biphasic change in left ventricular (LV) systolic pressure, with an initial fall followed by a prolonged rise, but the alterations were statistically significantly more pronounced with metrizoate than with iopentol. The changes in LV end-diastolic pressure (p = 0.023), and LV negative dP/dt (p = 0.002) were significantly more pronounced with metrizoate than with iopentol. Cardiac output and heart rate increased more with metrizoate, while stroke volume was equally increased by both agents. A prolonged increase in the QT-interval, throughout the 10-min observation period, was seen only after injection of metrizoate (p = 0.0006 for comparison between contrast media). CONCLUSION: Iopentol was well tolerated and induced markedly less severe hemodynamic and electrocardiographic alterations than did metrizoate in patients with severe coronary heart disease.

Diagnosis of small infrarenal aortic aneurysms by ultrasonography.

OBJECTIVE: Localized dilatation of the infrarenal aorta is currently assessed by comparison with the suprarenal aorta using a diameter ratio > 1.5 as an index of aneurysm. However, the bulging may be underestimated when there is concomitant enlargement of the suprarenal aorta and enhanced tapering of the aorta toward the bifurcation. Therefore, we studied an alternative reference point closer to the aneurysm. EXPERIMENTAL DESIGN: Prospective ultrasound study of localized infrarenal aortic dilation where its diameter is compared to 1) suprarenal aorta just above the orifices of the renal arteries and (2) infrarenal aorta at the upper margin of the aortic dilatation. PATIENTS: 91 consecutive ambulatory patients (66 men and 25 women, mean age 69 yrs) with a localized infrarenal aortic dilatation of > or = 3.0 cm in diameter. RESULTS: Mean diameter of the aortic bulges was 4.5 +/- 0.13 (SD) cm in males vs 4.0 +/- 0.73 cm in the females, (NS). The diameter ratio dilatation/suprarenal aorta exceeded 1.5 in 96% of the patients with an aortic bulging > or = 4.0 cm (n = 53) as compared to only 55% when the diameter was 3.0 to 3.9 cm (n = 38), p < 0.0001. However, when the aorta immediately above the dilated part was used as size reference the number of aortic bulges with a relative size of > 1.5 increased from 55% to 87% (p < 0.001). CONCLUSIONS: The degree of aortic bulging may be underestimated when the diameter of the dilated area is compared to that of the suprarenal aorta instead of the aorta immediately proximal to the dilatation, especially in small dilatations located near the aortic bifurcation.

Plasma cardiac natriuretic peptide determination as a screening test for the detection of patients with mild left ventricular impairment.

OBJECTIVE: To determine the usefulness of measuring the cardiac natriuretic peptides, atrial natriuretic factor, N-terminal pro-atrial natriuretic factor, and brain natriuretic peptide, as screening tests for identifying patients with mild left ventricular impairment. DESIGN: Cross-sectional evaluation of the diagnostic accuracy of the cardiac natriuretic peptides. SETTING: Cardiac catheterisation unit, Norwegian central hospital. PATIENTS: A consecutive series of 254 patients undergoing diagnostic left-sided cardiac catheterisation. One hundred and twenty eight of these patients had a history of previous myocardial infarction. MAIN OUTCOME MEASURES: The presence of normal and impaired left ventricular function, as evaluated by logistic regression analysis and estimation of the area under the receiver operating characteristic (ROC) curve (an index of overall diagnostic accuracy). Ventricular function was assessed by the measurement of left ventricular end diastolic pressure and angiographically determined left ventricular ejection fraction. RESULTS: Logistic regression analysis showed that plasma brain natriuretic peptide was the best predictor of increased left ventricular end diastolic pressure (> or = 15 mm Hg) (P < 0.001), decreased left ventricular ejection fraction (< or = 45%) (P < 0.001), and the combination of left ventricular ejection fraction < or = 45% and left ventricular end diastolic pressure > or = 15 mm Hg (P < 0.001). The areas under the ROC function for the detection of left ventricular dysfunction were 0.789 for brain natriuretic peptide, 0.665 for atrial natriuretic factor, and 0.610 for N-terminal pro-atrial natriuretic factor. CONCLUSIONS: Plasma brain natriuretic peptide seemed to be a better indicator of left ventricular function than plasma atrial natriuretic factor or N-terminal pro-atrial natriuretic factor. However, the overall diagnostic accuracy of circulating atrial natriuretic factor, N-terminal pro-atrial natriuretic factor, and brain natriuretic peptide as indicators of normal and impaired ventricular function in an unselected group of patients with coronary heart disease and a high frequency of previous myocardial infarction was relatively modest.

Right ventricular size and function as assessed by echocardiography and angiography in patients with different volume load.

A comparative study of right ventricular (RV) function, assessed by echocardiography and angiography, undertaken in 20 patients, 10 of whom had atrial septal defects (ASDs) and 10 had various other heart diseases. All of the measured echocardiographic variables of RV size, apart from RV length, were larger in the patients with ASD. When assessed by multiple regression analysis, the RV M-mode dimension was an independent variable of RV angiographic end-diastolic volume (EDV) in patients without RV volume load (R = 0.92, R2 = 0.85, p < 0.001). In the patients with ASD, echocardiographic RV end-diastolic area was an independent variable of angiographic RVEDV (R = 0.75, R2 = 0.55, p < 0.05), whereas M-mode dimension had a weaker correlation (r = 0.29). The agreement between RV ejection fraction (RVEF) obtained by echocardiography and angiography was moderate in both patient groups. However, fractional area change and fractional length change could not estimate RVEF better. Thus care should be taken to use single measurements and derivatives as the only parameters of RV size and function.

[Marfan syndrome. Cardiovascular manifestations diagnosed by echocardiography]. / Marfans syndrom. Kardiovaskulaere manifestasjoner diagnostisert med ekkokardiografi.

Echocardiographic and clinical evaluation was undertaken in 33 adult patients with Marfan syndrome. Cardiovascular manifestations were found in 32 (97%), mitral valve prolapse in 23 (70%) and dilated aortic root (> or = 21 mm/m2) in 26 patients (79%). The aortic root diameter was 58-85 mm in six patients with proximal aortic dissection, 57-76 mm in four patients undergoing elective surgery and 35-49 mm in conservatively treated patients. Average age at surgery was 28 years. Echocardiography with Doppler is the method of choice for diagnosis and control of patients with Marfan syndrome.

Ultrasound measurement of the luminal diameter of the abdominal aorta and iliac arteries in patients without vascular disease.

PURPOSE: The purpose of this study was to establish ultrasonographic criteria for the normal size of the abdominal aorta and iliac arteries in patients without vascular disease. METHODS: The luminal diameters of the proximal and distal abdominal aorta and the common iliac arteries were measured by ultrasonography in 160 patients (15 to 89 years) who were without known vascular disease. RESULTS: In patients above 50 years of age the distal aorta, which most often is involved in aneurysmatic dilations, measured 16.8 +/- 2.9 mm in men and 14.6 +/- 1.9 mm in women (p < 0.001). The diameter of the iliac artery in these patients was 10.1 +/- 2.0 mm in men and 9.2 +/- 1.3 mm in women (p < 0.001). The usually present gradual narrowing of the aorta toward the bifurcation was replaced by a slight increase (1 to 2 mm) in 5% of the men and 6% of the women. Focal areas of aortic enlargement, however, were not observed. In multivariate analysis, including age, height, body weight, and sex, the distal aortic diameter was significantly correlated only to age (r = 0.46; p < 0.001) and sex (r = -0.29; p < 0.001). With aging the mean of the proximal and distal aortic diameters increased by 0.08 and 0.05 mm/yr, respectively. Also correlated with age was a linear reduction in systolic expansion (r = -0.73; p < 0.001). CONCLUSIONS: Enlargement of the distal aorta and common iliac artery should be considered when (1) the luminal diameters in men exceed 23 and 14 mm, respectively, and in women 19 and 12 mm, respectively, (2) the ratio of the proximal and distal aortic diameter exceeds 1.1, and (3) there is demonstration of focal enlargement.

Hemodynamic status in repaired tetralogy of Fallot assessed by Doppler echocardiography and cardiac catheterization. Comparisons with healthy subjects and elucidation of factors associated with cardiorespiratory function.

Thirty-four patients were studied after corrective surgery for tetralogy of Fallot (mean follow-up 10 years) and compared with healthy matched controls. All underwent Doppler echocardiography, spirometry and treadmill exercise test. Post-operative cardiac catheterization had been performed on 26 (76%) of the patients and showed poor hemodynamic results in four (15%). Significant correlations of pressure gradients obtained from catheterization and estimated by Doppler echocardiography were right ventricular to right atrial (r = 0.77), pulmonary outflow (r = 0.75), pure valvular pulmonary outflow (r = 0.94) and diastolic pulmonary pressure gradients (r = 0.53). Pulmonary outflow gradients and right ventricular to right atrial pressure gradients estimated from tricuspid regurgitation jets were significantly increased in the patients. Diastolic pulmonary artery pressure, vital capacity and ventilatory anaerobic threshold were independent factors of maximal oxygen consumption. It is suggested that Doppler-derived diastolic pulmonary artery pressure, lung function studies and exercise testing with assessment of the ventilatory anaerobic threshold should be included in follow-up after repair of Fallot's tetralogy.

Effects of impaired lung function and pulmonary regurgitation on maximal exercise capacity in patients with repaired tetralogy of Fallot.

Long-term haemodynamic results and exercise capacity were studied in 34 patients with tetralogy of Fallot (24 men and 10 women) repaired 10.0 +/- 4.9 (mean +/- SD) years previously and compared to 34 healthy matched controls. All subjects were studied by resting spirometry, echocardiography and a symptom limited treadmill exercise test (modified Bruce protocol). The maximal oxygen consumption was 38.2 +/- 8.0 ml.kg-1.min-1 in patients and 48.1 +/- 8.1 ml.kg-1.min-1 in the control group (P < 0.001). Reduced maximal oxygen consumption was found in patients with low vital capacity (VC) and pulmonary regurgitation (PR). The ventilatory anaerobic threshold (VAT) was 23.8 +/- 0.6 ml.kg-1.min-1 and 29.9 +/- 0.6 ml.kg-1.min-1 in patients and controls, respectively (P < 0.001). VC was 3.4 +/- 1.21 in patients and 4.0 +/- 1.31 in controls (P < 0.02). In the patients, maximal ventilation was reduced and at submaximal exercise, the breathing frequency increased. Heart rates during exercise were similar in patients and controls. Tricuspid regurgitation (TR) was detected in 20 patients (58.8%); however, the exercise capacity was not reduced. Thus, impaired exercise capacity in tetralogy of Fallot is partly due to reduced resting lung function, pulmonary regurgitation and low ventilatory anaerobic threshold.

Addition of sodium to the nonionic contrast medium iohexol during coronary angiography in man. Lack of electrocardiographic or hemodynamic effects.

It has recently been claimed that lack of sodium in nonionic contrast media may increase the risk of ventricular arrhythmias during coronary angiography. Thus, the influence of sodium addition to the nonionic contrast medium iohexol was studied in 75 patients with severe coronary heart disease. The study design was randomized, parallel and double-blind, and iohexol was given either with or without addition of NaCl (28 mmol/l). Both formulations induced a transient drop in arterial blood pressure, and prolongation of the QT interval and QRS duration at 10 s only (p less than 0.01). The electrical QRS axis was significantly changed by the coronary artery injections after 10 s, but not later. No differences between iohexol with and without NaCl were observed for any of the variables studied. No serious arrhythmias were observed. Thus, the addition of NaCl (28 mmol/l) to iohexol did not influence the electrocardiographic or hemodynamic changes induced by iohexol during coronary angiography.

Effects of respiration on right ventricular size and function: an echocardiographic study.

The effects of quiet respiration and body position on right ventricular (RV) size and function were assessed by two-dimensional (2DE) and M-mode echocardiography in 15 healthy children. All end-diastolic echocardiographic dimensions, areas, and volumes increased slightly but significantly with inspiration. At end-systole similar changes were found. RV ejection fractions were significantly higher during inspiration, as were stroke volume indices. RV dimensions also increased from supine to left lateral decubitus position. Thus, our results indicate a need for standardization of 2DE and M-mode measurements not only for body position, but also for respiratory phase when used to assess RV size and function.

[Angina pectoris after coronary angioplasty. Restenosis or partial revascularization]. / Angina pectoris etter koronar angioplastikk. Restenose eller unfullstendig revaskularisering.

Percutaneous transluminal coronary angioplasty (PTCA) was performed on 115 consecutive patients with angina pectoris and the results were evaluated after an average of 100 days by means of bicycle exercise test and coronary angiography. Complete revascularization was achieved in 75% of the patients. Restenosis occurred in 23%. A good symptomatic effect was found in 90% of the patients with complete revascularization and in 72% of the patients with partial revascularization. Recurrence of angina pectoris 4-8 weeks after PTCA is a predictor of restenosis. Absence of angina and a negative bicycle exercise test 3-4 months after PTCA are strong predictors of the absence of restenosis.

Effect of timolol on cardiopulmonary exercise performance in men after myocardial infarction.

The effect of the nonselective beta blocker timolol on maximal cardiopulmonary exercise performance was evaluated in 28 men with previous myocardial infarction without effort angina (mean age 63 +/- 8 years). Patients were randomized to placebo or timolol (10 mg twice daily) for 4 weeks and then crossed over to the alternative therapy in a double-blind manner. At the completion of each treatment period, patients underwent symptom-limited maximal cardiopulmonary exercise on a cycle ergometer. Exercise time, heart rate, oxygen consumption (VO2), oxygen (O2) pulse and respiratory exchange ratio were measured at peak exercise and at a submaximal exercise level defined at a respiratory exchange ratio of 1.00. Timolol treatment reduced peak heart rate from 153 +/- 11 to 102 +/- 14 beats/min (-33%, p less than 0.001). Exercise time decreased from 680 +/- 91 to 633 +/- 78 seconds (-7%, p less than 0.001). Peak VO2 decreased from 25.3 +/- 4.7 to 21.4 +/- 3.5 ml/min/kg (-15%, p less than 0.001). O2 pulse increased from 12.9 +/- 1.9 to 16.7 +/- 2.3 ml/beat (+29%, p less than 0.001). Peak respiratory exchange ratio did not change significantly, indicating comparable effort. At submaximal exercise, defined at a respiratory exchange ratio of 1.00, there was no difference in exercise time between placebo and timolol. Heart rate decreased with timolol compared with placebo, from 126 +/- 16 beats/min by 31% (p less than 0.001), VO2 decreased from 18.5 +/- 4.3 ml/min/kg by 10% (p less than 0.001), O2 pulse increased from 11.5 +/- 2.0 ml/beat by 30% (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)