Correlation of ST-segment "hump sign" during exercise testing with impaired diastolic function of the left ventricle.

BACKGROUND: The appearance of a discrete upward deflection of the ST segment, termed the ST hump sign during exercise testing has been associated with resting hypertension and exaggerated blood pressure response to exercise. OBJECTIVE: We investigated the correlation between the presence of hump sign during exercise testing with coexisting impaired diastolic function of the left ventricle (LV) at these patients. METHODS: We formed a cohort of 237 nonconsecutive patients (140 males, 41 +/- 5 years old) having undergone a treadmill test, according to the Bruce protocol, which divided into 2 groups: group A, including 130 patients which presented ST-segment hump sign at any of the leads of the electrocardiograms recorded during exercise, and group B, including 107 patients that didn't. All patients subsequently underwent an echocardiographic estimation of the LV diastolic function, using conventional and Tissue Doppler Imaging techniques. RESULTS: From 237 patients included in our study, 106 had echocardiographic signs of diastolic LV dysfunction. Among them, the appearance of ST hump sign at the peak of exercise testing was observed in 93 patients (88%), particularly in the inferior and lateral leads, while no ST hump sign was observed only in 13 patients (12%) with impaired diastolic LV function. CONCLUSIONS: The appearance of ST segment hump sign during exercise testing is strongly correlated with diastolic LV dysfunction and can be used as an exercise electrocardiographic index of diastolic LV dysfunction, independently from the echocardiographic study.

Duration of treadmill exercise testing combined with QRS score predicts adverse cardiac outcome at long-term follow-up.

OBJECTIVE: Total exercise duration and abnormal QRS score values are treadmill exercise testing (TET) prognostic parameters that have been shown to be significantly and independently associated with cardiac mortality. We evaluated the prognostic value of a new index (M score, Michaelides score) incorporating TET duration and QRS score values in a simple index. METHODS: In this study, we included 626 patients, who underwent TET and coronary arteriography. Cardiac catheterization showed the presence of coronary artery disease in 64.3% of these patients. The M score was calculated by adding the value of the Athens QRS score to the duration of TET (in minutes). The outcome measure was a composite of myocardial infarction or death. Patients were prospectively followed for 38+/-21 months (median 36 months). RESULTS: The composite endpoint was more frequent among the patients of the 1st quartile (M-score values <-5.8). In univariate analysis, mortality of the first-quartile patients was significantly higher (14 vs. 1.1%, P<0.001). In multivariate Cox's regression analysis for age, sex, diabetes, smoking status, hypertension, hypercholesterolemia, maximum ST depression at TET, angina during TET, coronary artery disease on angiography, and echocardiographic left ventricular ejection fraction, the first quartile of M-score values was found to be independently associated with the composite endpoint (relative risk = 3.26, 95% confidence interval = 2.01-5.29, P<0.001). CONCLUSION: This study shows that a new index termed the M score, which incorporates QRS score and exercise duration, predicts mortality and occurrence of myocardial infarction at long-term follow-up of high-risk individuals, independently of TET-induced ST-segment changes.

ST segment "hump" during exercise testing and the risk of sudden cardiac death in patients with hypertrophic cardiomyopathy.

BACKGROUND: The appearance of a discrete upward deflection of the ST segment termed "the ST hump sign" (STHS) during exercise testing has been associated with resting hypertension and exaggerated blood pressure response to exercise. OBJECTIVE: We investigated the prevalence and clinical significance of this sign in a population of patients with hypertrophic cardiomyopathy. METHODS: Eighty-one patients with hypertrophic cardiomyopathy (HCM) who underwent cardiopulmonary exercise testing were followed in a retrospective cohort study for a mean period of 5.3 years. RESULTS: The appearance of the STHS at the peak of exercise testing was observed in 42 patients (52%), particularly in the inferior and the lateral leads. Patients with the STHS had higher fractional shortening and maximum left ventricular wall thickness and exhibited more frequently outflow tract gradient >30 mmHg at rest. Furthermore, the presence of STHS was a strong independent predictor of the risk of sudden cardiac death (SCD), as the latter occurred in eight of the patients with this sign (8/42, 19%) and in none of the patients without it (0/39, 0%) (P < 0.001). CONCLUSION: The appearance of a "hump" at the ST segment during exercise testing appears to be a risk factor for SCD in patients with HCM. However, further studies are necessary to validate this finding in larger populations and to elucidate the mechanism of the appearance of the "hump."

Correlation of modification of heart rate recovery with adaptation to myocardial ischemia in a model of sequential exercise testings.

BACKGROUND: Heart rate recovery (HRR) has been identified as a reliable predictor of cardiac mortality, correlated with autonomic tone. In a model of sequential exercise testings, we investigated the reproducibility of HRR and the association between HRR modification and myocardial adaptation to ischemia. METHODS: We studied 128 patients (mean age 62 +/- 9 years, 83% males) with angiographically documented coronary artery disease (CAD) and a first positive exercise testing, who agreed to undergo a second exercise testing after 24 hours. RESULTS: HRR was increased from 25 +/- 10 beats/min at the first exercise testing to 30 +/- 13 beats/min at the second exercise testing (P < 0.001). Thereafter, participants were divided into two groups: Group I comprised 88 patients who presented augmentation of the HRR in the first compared to the second exercise testing, while group II comprised 40 patients who presented unchanged or reduced HRR. The rate-pressure product (RPP) at 1 mm ST-segment depression (ischemic threshold) at the second compared to the first exercise testing were significantly improved in group I patients (2345 +/- 3429 mmHg/min), while it was worsened in group II patients (-630 +/- 2510 mmHg/min) (P < 0.001). CONCLUSIONS: In a model of sequential exercise testings, myocardial adaptation to exercise-induced ischemia was associated with favorable modification of HRR.

QRS score improves diagnostic ability of treadmill exercise testing in women.

OBJECTIVE: The accuracy of treadmill exercise testing to detect coronary artery disease is limited in women. This study was undertaken to evaluate whether QRS score can improve the accuracy of treadmill exercise testing in women. METHODS: The study population consisted of 114 women with angina-like symptoms, who underwent both treadmill exercise testing and coronary angiography. The impact of QRS score on the standard ST-segment based diagnostic ability of treadmill exercise testing to detect coronary artery disease was studied. RESULTS: Incorporation of QRS score in standard ST-segment diagnostic criteria significantly enhanced sensitivity (from 59 to 80%), specificity (from 40 to 94%) and diagnostic accuracy (from 50 to 87%) of treadmill exercise testing. The QRS score was shown to reduce significantly the false-positive results from 60 to 6%. Furthermore, QRS score accuracy was correlated with the extent of coronary artery disease. The diagnostic ability of QRS score was greater both among patients with normal and impaired systolic function of the left ventricle. CONCLUSIONS: QRS score can improve the limited diagnostic accuracy of treadmill exercise testing in women, by predominantly decreasing the high prevalence of false-positive results.

Hypertensive patients with false-positive thallium-201 scintigraphic results in the infero-posterior wall are in high risk for coronary artery disease development.

BACKGROUND: It has been previously postulated that Thallium-201 (Tl201) scintigraphy is characterized by relatively low specificity in hypertensive patients. This study was undertaken to assess any possible influence of false-positive scintigraphic results on the prognosis of hypertensive patients. METHODS: The study group comprised 179 consecutive hypertensive patients (128 men and 51 women), aged 50+/-7 years, who underwent exercise Tl(201) scintigraphy and coronary angiography (patients with normal scintigraphic results underwent coronary angiography due to persistent angina-like symptoms). All patients with normal coronary arteries underwent a second Tl201 scintigraphy within 36+/-6 months. Patients with reversible ischemia in the second scintigraphy underwent also a second coronary angiography. RESULTS: Coronary artery disease (CAD) was detected in 78 (44%) patients, while the rest 101 (56%) patients had normal coronary arteries. Abnormal scintigraphic results were revealed in 66 (85%) patients with CAD and in 38 (38%) patients without CAD. Twenty-two (58%) of the 38 hypertensive patients with false-positive scintigraphic results presented reversible ischemia of the infero-posterior wall of the left ventricle. Coronary artery disease was detected in 7 (32%) of these patients during the follow-up period. CONCLUSIONS: Hypertensive patients with normal coronary arteries and false-positive scintigraphic results usually present with reversible ischemia of the infero-posterior wall of the left ventricle. This group of patients seems to be at increased risk of developing CAD in a long-term follow-up period.

The aortic distensibility alteration is an index of influence of ischemic preconditioning to myocardial performance.

BACKGROUND: Ischemic preconditioning (IP) is a cardioprotective phenomenon, induced by brief episodes of myocardial ischemia, which is supposed to affect not only the myocardium, but also the entire cardiovascular system. Considering that patients with coronary artery disease (CAD) have also been described to present impaired aortic mechanical properties, we tried to investigate the possible influence of the late phase of IP on aortic distensibility in patients with CAD. METHODS: Fifty patients, aged 48 to 72 (mean, 57+/-6 years), with angiographically confirmed CAD and exercise-induced myocardial ischemia, underwent two treadmill exercise testings (ETs). The second ETs was performed the next day. Thallium-201 scintigraphy was performed during the first and the second ET. Aortic distensibility was evaluated before each exercise testing by a non-invasive technique, using two-dimensional guided M-mode transthoracic echocardiography and arterial pressure was measured simultaneously at the brachial artery by sphygmomanometry. RESULTS: The patients were divided in 2 groups according to the extent of myocardial ischemia at peak exercise of the second test, compared to the first test. In 35 (70%) of the studied patients ischemia signs were reduced during the second ET (Group A), while in the rest 15 (30%) of the patients (Group B) no improvement or even worsening of the observed ischemia signs was demonstrated by the studied exercise parameters and the extent of myocardial ischemia in thallium-scintigraphy. Increased aortic distensibility during the second measurement was found in 33 (94%) of the 35 patients of Group A but only in 1 (7%) of the 15 patients of Group B. Aortic distensibility was found to be significantly improved in patients of Group A, while it was found to be worsened in Group B patients. CONCLUSIONS: The aortic distensibility alteration could be used as an index of influence of ischemic preconditioning to exercise-induced myocardial ischemia, which could be considered indicative of the systemic effects of IP in humans.

Significance of QRS duration changes in the evaluation of ST-segment depression presenting exclusively during the postexercise recovery period.

BACKGROUND: The aim of this study was to evaluate the contribution of QRS prolongation in the diagnosis of coronary artery disease (CAD) in patients with exercise-induced ST-segment depression exclusively during the recovery period. METHODS: The study population consisted of 107 patients (90 males and 17 females) aged 39-70 (mean 59 +/- 7) years who underwent a treadmill exercise test using Bruce protocol and presented ST-segment depression limited to the recovery period. Angiographic data were available for all studied patients. RESULTS: Among studied patients, 74 (69%) were found to have hemodynamically significant CAD, while the remaining 33 (31%) had normal coronary arteries. Concomitant QRS prolongation was revealed in 61 (82%) of the patients with angiographically documented CAD, while in 13 (18%) patients QRS duration remained unchanged. On the contrary, only 4 (12%) of the 33 patients with normal coronary arteries showed prolonged QRS duration during ST depression, while in the remaining 29 (88%) QRS duration remained unchanged. CONCLUSIONS: The evaluation of the concomitant QRS duration changes may discriminate patients with truly ischemia-induced ST-segment depression limited to the recovery period.

Q fever endocarditis masquerading as Mixed cryoglobulinemia type II. A case report and review of the literature.

BACKGROUND: The clinical manifestations of Q fever endocarditis are protean in nature. Mixed cryoglobulinemia type II is rarely a facet of the presenting clinical manifestations of Q fever endocarditis. CASE PRESENTATION: We report a case of a 65-year-old pensioner with such an association and review the literature. As transesophageal echocardiograms are usually normal and blood cultures are usually negative in Q fever endocarditis, many of the manifestations (fever, rash, glomerulonephritis/evidence of renal disease, low serum C4 complement component, presence of mixed type II cryoglobulin, constitutional symptoms as arthralgias and fatigue) can be attributed to Mixed cryoglobulinemia type II per se. The use of Classic Duke Endocarditis Service criteria does not always suffice for the diagnosis of Q fever. CONCLUSION: The application of the modified criteria proposed by Fournier et al for the improvement of the diagnosis of Q fever endocarditis will help to reach the diagnosis earlier and thus reduce the high mortality of the disease. We would like to stress the importance of ruling out the diagnosis of Q fever endocarditis in cases of mixed type II cryoglobulinemia.

Role of right-sided chest leads in the detection of multivessel coronary artery disease in patients with extended Q-wave anterior myocardial infarction.

OBJECTIVE: To evaluate the improvement of diagnostic ability of exercise testing to detect multivessel coronary artery disease in patients with extended Q-wave anterior myocardial infarction, using additional right-sided chest leads. METHODS: Fifty-two consecutive patients with Q-wave anterior myocardial infarction underwent exercise testing, using the standard 12 and the additional right-sided (V3R, V4R, V5R) chest leads, thallium-201 scintigraphy and coronary arteriography. RESULTS: Twenty-one (40%) patients had one-vessel disease, 18 (35%) had two-vessel disease and 13 (25%) had three-vessel disease. The sensitivities of the standard 12-lead exercise testing and its combination with the additional right-sided chest leads were 24% (5/21) versus 28% (6/21) for the detection of one-vessel disease (P: NS), 33% (6/18) versus 83% (15/18) for the detection of two-vessel disease (P<0.05) and 38% (5/13) versus 92% (12/13) for the detection of three-vessel disease (P<0.05), respectively. In thallium-201 scintigraphy, 29 of the 31 (94%) patients with multivessel coronary artery disease demonstrated reversible ischemia. The usual 12-lead exercise testing could detect ischemia in 11 (35%) of these 31 patients, while the addition of the right-sided chest leads could detect ischemia in 27 (87%) of them (P<0.05). CONCLUSIONS: The additional right-sided chest leads significantly improve the low sensitivity of the usual exercise testing to detect multivessel coronary artery disease in patients with previous extended Q-wave anterior myocardial infarction.

QRS score versus ST-segment changes in patients undergoing Tl-201 scintigraphy using dipyridamole infusion.

BACKGROUND: ST-segment changes after dipyridamole infusion followed by handgrip isometric stress lack diagnostic value, because of the low sensitivity for the detection of coronary artery disease (CAD). In addition, an abnormal QRS score during exercise had a greater diagnostic ability than ST-segment changes to detect CAD. This study was undertaken to compare QRS score values with ST-segment changes during thallium 201 scintigraphy via dipyridamole infusion. METHODS AND RESULTS: In this study 128 patients (101 men and 27 women), aged 53 to 72 years (mean, 59 +/- 8 years), underwent Tl-201 scintigraphy after dipyridamole infusion and handgrip isometric stress, as well as coronary angiography. QRS score values and ST-segment changes after dipyridamole infusion and handgrip isometric stress were also estimated. CAD was detected in 96 patients (75%), whereas normal coronary arteries were found in 32 (25%). According to scintigraphic data, 48 patients (37%) had no reversible perfusion defects whereas 80 (63%) had at least 1 reversible perfusion defect. Sensitivities for an abnormal QRS score and ST-segment deviation were 68% versus 18% ( P < .01) for detection of CAD and 75% versus 19% for detection of myocardial ischemia ( P < .01), respectively. Similar specificities were found ( P = not significant). CONCLUSIONS: An abnormal QRS score significantly improves the low sensitivity of ST-segment changes for the detection of myocardial ischemia and CAD by use of Tl-201 scintigraphy with dipyridamole infusion and handgrip isometric stress.

Exercise testing in asymptomatic patients with heterozygous familial hypercholesterolaemia.

OBJECTIVE: Familial hypercholesterolaemia (FH) is a frequent genetic disorder in Europe, affecting one in 500 people in its heterozygous form. Both homozygous and heterozygous forms are correlated with increased incidence of cardiovascular events. METHODS: We investigated clinical and biochemical parameters possibly associated with the results of exercise testing (ET) in asymptomatic patients with heterozygous FH. The study population was derived from outpatients of the Lipid Center in our department and consisted of 194 patients with heterozygous FH who had no medical history of coronary artery disease (CAD) or angina-like symptoms and who had agreed to undergo ET. RESULTS: Sex, body mass index, smoking status, diabetes mellitus, family history of CAD, presence of xanthomas and total cholesterol, triglyceride, low-density and high-density lipoprotein cholesterol, apolipoproteins A and B and lipoprotein (a) levels did not differ significantly between patients with positive and negative ET. Higher fibrinogen levels, arterial hypertension and family history of CAD were more frequent among patients with positive ET. However, in multivariate analysis adjusted for all the aforementioned variables, only high fibrinogen levels were significantly and independently associated with a positive result of ET. CONCLUSIONS: Lipid and coronary risk factor profiles do not seem to predict exercise-induced myocardial ischaemia in asymptomatic patients with heterozygous FH. However, in this high-risk population for cardiovascular events, fibrinogen levels are an independent predictor of positive ET. The adverse effects of FH on the cardiovascular system may be partly mediated by coagulability factors, whose role in the management of FH patients remains to be fully clarified.

Detection of multivessel disease post myocardial infarction using an exercise-induced QRS score.

OBJECTIVE: The aim of this study was to investigate the ability of Athens QRS score values to detect stenoses in other coronary arteries than the obstructed ones (which caused the myocardial infarction [MI]) in patients with a history of MI. METHODS: We studied 125 patients (93 males and 32 females, mean age 54 +/- 7 years [range 45-68 years]) with a history of MI (46 patients with anterior MI, 54 patients with inferior MI, 25 patients with lateral MI). All patients underwent treadmill exercise testing and coronary arteriography. RESULTS: Athens QRS score values were inversely related to the extent of CAD: -0.5 +/- 0.3 mm for patients with 1-VD (obstructed vessel), -3.4 +/- 2.2 mm for patients with 2-VD (obstructed vessel and stenosis in another vessel), and -5 +/- 1.8 mm for patients with 3-VD (obstructed vessel and stenoses in two more vessels). The ROC curves for the detection of multivessel disease showed that the area under the curve for QRS score values < -3 mm is significantly higher than the curve for ST-segment depression > or = 1 mm (0.948 vs 0.792, P < 0.001). CONCLUSIONS: Values of the Athens QRS score less than -3 may distinguish single- from multivessel coronary artery disease in patients with a history of MI.