ABSTRACT
OBJECTIVE: To investigate the dispersion of repolarization variables in patients with rheumatoid arthritis (RA). METHODS: Electrocardiography (ECG) and Doppler echocardiography were performed on 40 patients with RA, which were divided into two groups according to the duration of disease and in 48 healthy controls. RESULTS: All patients had significantly longer QT dispersion (QTd) and corrected QT dispersion (QTc-d) values (p<0.05). The mean values of diastolic function variables were significantly different in all patients compared to healthy controls (p<0.05). There were no statistically significant differences between patient groups in terms of diastolic function variables except IVRT. However, QTd and QTc-d were significantly longer in patients with disease duration over 5 years (p<0.05). CONCLUSION: We conclude that repolarization heterogeneity and diastolic dysfunction are commonly seen in RA, and QTd is significantly longer in those patients with a disease duration over 5 years compared to those with new onset RA.
Subject(s)
Arthritis, Rheumatoid/complications , Long QT Syndrome/etiology , Arthritis, Rheumatoid/physiopathology , Echocardiography, Doppler/methods , Electrocardiography/methods , Female , Humans , Joints/physiopathology , Long QT Syndrome/physiopathology , Male , Middle Aged , Severity of Illness IndexABSTRACT
AIM: Dobutamine as a predominant beta-1 agonist increases heart rate and myocardial contractility and at sufficient high doses, it also increases systolic blood pressure. This study was undertaken to describe instances of paradoxical hypotension during dobutamine infusion for TI-201 myocardial perfusion SPECT study and the relationship between scintigraphic findings and hypotension occurred during dobutamine infusion. METHODS: In 201 consecutive patients unable to perform adequate exercise, dobutamine TI-201 myocardial SPECT was performed. Dobutamine was infused starting from 10 micrograms/kg/min increasing to 40 micrograms/kg/min. Paradoxical hypotension was defined as a decrease in systolic blood pressure > or = 20 mmHg compared with baseline study. RESULTS: Paradoxical hypotension was observed in 40 patients (Group A) out of 201 (19.9%) while no significant change in systolic blood pressure was detected in the remaining 161 patients (Group B). Mean maximum fall in systolic blood pressure was 39 +/- 18 mmHg (range: 20-90). In 33 of 40 patients (83%) with paradoxical hypotension, scintigraphy was normal compared to 131 (81%) of the remaining 161 patients. In patients of Group A, angiography, echocardiography and tilt table tests were performed in 13, 11 and 6 patients respectively. Nine of 13 angiographic evaluations (69%), 10 of 11 echocardiographic evaluations (91%), all of the tilt table tests were normal. Additionally, all of the patients of Group A were clinically followed up at least 6 months after the myocardial perfusion scintigraphy. None of the patients had a cardiac event except one patient during the follow-up period. CONCLUSION: Paradoxical hypotension during dobutamine infusion for myocardial scintigraphy is not an uncommon finding and up to 19.9% patients may develop such hypotension. To maximize test safety, precautions should be taken during dobutamine myocardial stress test, since remarkable decrease in systolic blood pressure may occur. Unlike hypotension occurring with exercise test, hypotension response to dobutamine is not always a marker for coronary artery disease.
Subject(s)
Adrenergic beta-Agonists/adverse effects , Coronary Disease/diagnostic imaging , Dobutamine/adverse effects , Heart/diagnostic imaging , Hypotension/chemically induced , Thallium Radioisotopes , Adrenergic beta-Agonists/administration & dosage , Adult , Aged , Blood Pressure/drug effects , Cardiac Catheterization , Coronary Angiography , Dobutamine/administration & dosage , Echocardiography , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Tomography, Emission-Computed, Single-Photon/methodsABSTRACT
The aim of this study was to examine the value of an additional atropine injection in patients who do not achieve an adequate heart rate during dobutamine infusion for myocardial perfusion SPET (single photon emission tomography). Patients undergoing dobutamine myocardial SPET who failed to achieve > or = 85% of their age-predicted maximal heart rate at the end of dobutamine infusion (D protocol) had a second dobutamine myocardial SPET study on a separate day with the addition of an atropine injection during the dobutamine infusion (D + A protocol). Twenty-nine patients were studied. 201Tl was used in 27 patients and 99Tc(m)-MIBI in two patients. All patients underwent coronary angiography and significant coronary artery disease was found in 19 of 29 patients. The mean heart rate obtained at the peak of dobutamine infusion in the D + A protocol was significantly higher than that in the D protocol (153.8 +/- 13.8 vs 117.5 +/- 15.3 beats min[-1]). The D + A protocol resulted in a higher diagnostic sensitivity for the detection of stenosed coronaries compared with the D protocol (87 vs 80%, P > 0.05) without changing the specificity (89% for both protocols). On the other hand, the frequency of side-effects and ECG changes during the D + A protocol was higher than that with the D protocol (32 vs 47). In conclusion, the addition of an atropine injection during dobutamine infusion resulted in a higher diagnostic sensitivity for identifying stenosed coronaries compared to dobutamine alone.
Subject(s)
Atropine , Chest Pain/diagnostic imaging , Dobutamine , Heart/diagnostic imaging , Tomography, Emission-Computed, Single-Photon/methods , Adrenergic beta-Agonists/administration & dosage , Adult , Aged , Atropine/administration & dosage , Atropine/adverse effects , Dobutamine/administration & dosage , Dobutamine/adverse effects , Drug Combinations , False Negative Reactions , False Positive Reactions , Female , Heart/drug effects , Heart Rate/drug effects , Humans , Infusions, Intravenous , Injections, Intravenous , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/physiopathology , Parasympatholytics/administration & dosage , Reproducibility of Results , Sensitivity and Specificity , Stress, Physiological , Systole/drug effects , Technetium Tc 99m Sestamibi , Thallium RadioisotopesABSTRACT
Although lipoprotein (a) [Lp(a)] has been shown to interfere with thrombolysis in vitro, its effects on thrombolytic therapy in patients with acute myocardial infarction (MI) are not clear. The authors evaluated 32 male patients ages thirty-five to seventy-five (mean fifty-two +/- ten) with the diagnosis of acute MI who underwent thrombolytic therapy with 1,500,000 units of intravenous streptokinase. All patients underwent coronary angiography within seven days of the infarction from which the thrombolysis in myocardial infarction (TIMI) flow grades of the infarct-related artery, coronary scores, and ejection fraction were determined. Anterior MI was found in 19 patients (59.4%), inferior MI in 12 (37.5%), and posterolateral MI in 1 patient (3.1%). They found that 6 patients (18.8%) had TIMI flow 0 to 1, and 26 patients (81.2%) had TIMI flow grade 2 or 3. The Lp(a) levels ranged from 0.1 to 60 mg/dL with a mean of 8.6 +/- 17 mg/dL. Eight (25%) of the patients had Lp(a) levels above 30 mg/dL. The TIMI flow rates were not found to be lower in patients with high Lp(a) levels (P > 0.05), and there was no significant correlation between the TIMI flow rates and the Lp(a) levels (r = 0.28). There was a good correlation between coronary scores and Lp(a) levels (r = 0.87). They conclude that although there is a good correlation between the extent of coronary atherosclerosis and Lp(a) levels, Lp(a) is not a strong predictor of the outcome of thrombolytic therapy.
