Multislice CT in emergency room management of patients with chest pain and medium-low probability of acute coronary syndrome

PURPOSE

The main cause of acute chest pain, which accounts for 6.5% of urgent medical examinations in emergency rooms in Italy, is acute coronary syndrome (ACS). We performed this prospective study to evaluate the diagnostic accuracy of a 16-channel computed tomography (CT) scanner with dedicated software in a group of patients with chest pain and medium to low risk of ACS.

MATERIALS AND METHODS

This study involved a selected group of 31 patients reporting chest pain with a medium to low probability of ACS, defined on the basis of preliminary tests [electrocardiogram (ECG) and serum cardiac markers]. Coronary angiography, performed within 24 h of MSCT, was used as the gold standard.

RESULTS

MSCT identified the presence of occlusions and significant (>50%) or nonsignificant stenoses in the main coronary segments, with a sensitivity of 65%, a specificity of 98.8%, a positive predictive value (PPV) of 81.2%, a negative predictive value (NPV) of 97.3% and an accuracy of 96.4%. Significant stenoses and occlusions were detected with a sensitivity of 71.4%, a specificity of 99.6%, a PPV of 93.7%, an NPV of 97.7% and an accuracy of 97.5%.

CONCLUSIONS

Due to its high NPV, this technique can rule out significant stenoses or coronary occlusions provided that image quality is excellent. In patients with a medium to low coronary risk, MSCT is a more accurate indicator of the need for coronary angiography than is exercise stress testing, which is less expensive but has lower predictive values.

Left main coronary artery disease. Clinical and angiographic features. A retrospective study regarding two groups of patients with left main coronary artery disease and three-vessel disease

BACKGROUND

The aim of this study was to assess the ability of clinical and instrumental features to identify patients with left main coronary artery disease (LMCD) compared with a three-vessel coronary artery disease group.

METHODS

A cohort of 70 patients with LMCD was matched with another one of 66 patients with three-vessel disease. A history of angina before angiography was similar in both groups; the higher degrees of stable angina and the forms of unstable angina were moderately prevalent in the group with LMCD.

RESULTS

In the last subgroup a significantly reduced incidence of previous acute myocardial infarction (AMI) was observed (p < 0.05). The resting electrocardiogram (ECG) showed higher incidence of atrial fibrillation (fa) and left bundle branch block (BBS) in the subjects with LMCD, with a statistic value (p < 0.05). The exercise test performed by a lot of patients appeared equally positive for inducible ischemia in the 2 groups. Significantly higher exercise peak load was achieved by the patients with three-vessel disease (p < 0.05). The coronary angiography showed a prevalence of right dominant circulation in the 2 groups; significantly the collateral circulation was more represented in the subjects with three-vessel disease (p < 0.05). Most patients with LMCD underwent a bypass coronary artery graft surgery (CABG surgery) more frequently than the ones with three-vessel disease (p < 0.01). In the former group the cardiovascular mortality within an average 2-year follow-up proved higher as to the latter group even if without statistic significance.

CONCLUSIONS

Nevertheless this retrospective study showed some limitations. Particularly the incidence of clinical and instrumental variables and their capacity to differentiate LMCD patients from those with three-vessel disease were not demonstrated.

[Bacterial endocarditis in pregnancy. Report of a clinical case diagnosed postpartum]

Bacterial endocarditis in pregnancy shows a low incidence; it is often associated with a prior history of rheumatic or congenital heart disease. In the large part of reports the illness tends to run a subacute course and to recognize a major frequency in the third trimester of pregnancy. We presented the case of a 29 year-old woman with mitral and aortic bacterial endocarditis. Transthoracic echocardiography performed one week after spontaneous delivery suggested valve vegetations. Antibiotic therapy turned out to be partially successful, in fact cerebral embolizations subsequently occurred. Conservative surgery appeared to be favourable and the patient shows a satisfactory present clinical state.

[Prognostic significance of thallium-201 scintigraphy in patients with previous myocardial infarct]

With the purpose of ascertaining the predictive value of residual myocardial ischemia, in stable clinical conditions at a distance after myocardial infarction, on the incidence of late cardiac events, we evaluated 55 patients 24.2 +/- 11.4 months after myocardial infarction with thallium-201 stress test imaging. All patients were either asymptomatic or with stable effort angina pectoris, well controlled with medical treatment. In the next follow-up period, whose duration has been 22.4 +/- 14.4 months, the incidence of unfavourable cardiac events, like unstable angina, reinfarction, coronary bypass surgery, sudden cardiac death has been monitored. Thirty-one patients (56.4%) presented a reversible perfusion defect (RPD) in one or more myocardial segments; 17 of these 31 showed cardiac events during follow-up. Only 2 patients of the remaining 24 without RPD had cardiac events, with a significant difference (p less than 0.01). The patients with RPD only in peri-infarct areas had a relatively smaller number of cardiac events, with respect to those patients with RPD also or only in distant areas. Fifteen of 21 patients with RPD in 2 or more segments manifested cardiac events, compared to 2 of 10 patients with RPD in only one segment (p less than 0.01). In 10/55 patients, increased lung uptake of thallium-201 activity was observed; 8 of them presented cardiac events (p less than 0.01). This analysis confirms the high predicting value of thallium-201 RPD imaging on the incidence of cardiac events in patients controlled at a distance after myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler study of precordial musical murmurs

Using phonocardiography, continuous- and pulsed-wave Doppler, 51 patients with precordial "musical" murmurs (49 with cardiac abnormalities) and 21 patients with noisy murmurs were examined. With M-mode echocardiography, fine fluttering of the structure generating the murmur was evident in 23 patients with musical murmurs and in 5 with noisy murmurs. A continuous-wave Doppler spectral signal characterized by parallel harmonics (Doppler musical signal) was evident in all patients with musical murmurs and in none with a noisy murmur. With pulsed-wave Doppler, the musical signal had less defined spectral features because of range ambiguity. Such a signal was experimentally reproduced by activating a diapason bathed in saline solution. The source of the musical murmur was established in all 51 patients by Doppler. The musical signal was associated with a valvular regurgitation signal in 36 patients and with a ventricular septal defect in 1 patient. The musical signal always disappeared when the pulsed-wave Doppler sample volume was placed 2 cm away from the generating structure. In 11 patients with musical murmur examined by color Doppler, no abnormal bidirectional flow signal was observed in the structures generating the signal. In 6 of the patients without valvular regurgitation, no flow disturbance was found. In conclusion, Doppler is valuable in determining the source of musical murmurs, and musical murmurs are caused by a vibrating structure even in the absence of flow turbulence.

[Echo-Doppler study of musical heart murmurs]

The origin of systolic or diastolic musical murmurs was investigated by means of echo-doppler examination in 51 patients with various cardiac diseases. In all cases a typical doppler spectrum was identified, showing bi-directional clusters of frequencies which were concentric in systole and parallel in diastole. The doppler audio signal was musical. A similar echo-doppler signal was obtained by a diapason vibrating in isotonic solution. These data allowed us to identify the site of the vibrating cardiac structure causing the typical echo-doppler spectrum and characteristic audio signal.

[Doppler echocardiography in assessing mechanical and biological heart valve prostheses]

The study was performed to assess Doppler echocardiographic features of mitral and aortic prosthetic valves of different types with both normal and abnormal function. Two hundred and twenty-three patients with 250 prostheses were studied. Two hundred eight valves (111 mitral, 95 aortic and 2 tricuspid) were considered to be functioning normally after clinical examination, phonocardiography and M-mode and 2D echocardiography. This group enabled us to define normal Doppler echocardiographic findings for different types of prosthesis. In mitral position, peak (p) and mean (m) gradients were lower for disc prostheses and higher for ball and biological prosthetic valves; values of effective orifice area (A), calculated by pressure half-time method, were lower for biological and ball prostheses and higher in disc valves. Results were as follows: St. Jude (p 10.6 mmHg, m 3.9 mmHg, A 2.7 cm2), Duromedics (p 10.6, m 4.3, A 2.8), Björk-Shiley (p 10.4, m 4, A 2.3), Omniscience (p 14.2, m 6.2, A 2.1), Starr-Edwards (p 15.9, m 5.4, A 2.1), Hancock (p 14.7, m 6, A 2), Carpentier (p 13.2, m 5.4, A 1.9). Mild regurgitation, considered "physiological", was found in 2/8 Carpentier valves and in 3/34 St. Jude prostheses. In aortic valves lower peak gradients were found in Lillehei (18.3 mmHg), St. Jude (23.8 mmHg), Björk-Shiley (26 mmHg), Duromedics (27 mmHg) and higher values in Starr-Edwards (30.2 mmHg), Hancock (30 mmHg) and Omniscience (35.5 mmHg) prostheses. Mild regurgitation, considered "physiological", was found in 17% of Omniscience valves, 21% of Hancock, 33% of Duromedics, 45% of St. Jude, 60% of Björk-Shiley prostheses. Hancock mitral valves implanted for over 7 years had a mean gradient higher than valves with a shorter period of implantation (7.6 vs 4.85 mmHg, p less than 0.1), whereas the effective orifice area was similar. Hancock aortic valves implanted for over 7 years had a peak gradient slightly higher than the other group (implantation less than 7 years previously), but the difference was not statistically significant. Forty-two valves (19 aortic and 23 mitral) were considered to be malfunctioning. Regurgitation Doppler signals of malfunctioning valves appeared different from those of "physiological" reverse flow; in the former cases forward gradient was higher than normal prostheses. In stenotic aortic prostheses, peak systolic gradient was greatly increased; in stenotic mitral prostheses, a very significant increase in mean gradient and a great decrease in effective orifice area were found. In 14 patients who underwent surgical re-operation and in the patient who died before operation, Doppler echocardiographic findings were confirmed.(ABSTRACT TRUNCATED AT 400 WORDS)

[Species of cooperia ranson, 1907, (nematoda: trichostrongylidae), parasite of bovines in the State of São Paulo, Brasil (author's transl)]

The authors verified for the first time in the State of São Paulo, Brazil, the presence of Cooperia curticei Giles, 1892 (Nematoda: Trichostrongylidae), parasitizing the small intestine of cattle at the Region of Alta Araraquarense.

[Cooperia curticei Giles, 1892 (nematoda: trichostrongylidae) parasite of goats (capra hircus) in the State of São Paulo, Brazil (author's transl)]

Cooperia curticei Giles, 1892 (Nematoda: Trichostrongylidae) is reported, for the first time, parasitizing the small intestine of goats (Capra hircus) in the State of São Paulo, Brazil. The animals came from the Region of the Alta Araraquarense. The spicules of the worms were well chitinized and measured, on the average, 153,68 micrometer with a standard error of 0,91 micrometer.