Evidence of walk-through phenomenon during echocardiographic dipyridamole stress test.

This case report deals with induced regional wall motion abnormalities that spontaneously disappeared during an echocardiographic stress test with dipyridamole. A patient underwent this test because of atypical chest discomfort and a positive result of exercise stress test. Transient septal, apical and anterior akinesia were observed after the first dose of dipyridamole, but they were short-lasting and did not return during the continuation of the test. Coronary angiography showed a critical stenosis of the left coronary artery. A mechanism similar to that responsible for the walk-through phenomenon might explain the observed findings. Thus stress echo with dipyridamole needs careful continuous monitoring, because transient wall motion abnormalities can otherwise be missed resulting in a false negative test.

Exercise technetium 99m sestamibi single-photon emission computed tomography late after coronary artery bypass surgery: long-term follow-up.

BACKGROUND AND HYPOTHESIS: The prognostic value of exercise technetium 99m sestamibi single-photon emission computed tomography (SPECT) imaging in patients with previous bypass surgery is unknown. The aim of our study was to assess the prognostic information obtained with exercise scintigraphy performed for routine follow-up or reappearance of symptoms. METHODS: We studied 75 patients referred to our Center at a mean of 38 +/- 53 months from the revascularization procedure and prospectively followed them for 38 +/- 24 months. RESULTS: Fifteen patients (20%) had events at follow-up: there were 4 cardiac deaths, 3 nonfatal acute myocardial infarctions, 8 late revascularization procedures (4 percutaneous transluminal angioplasty and 4 repeat bypass surgery). Univariate analysis identified a history of typical angina (p = 0.001), a clinically positive ergometric test (p = 0.009), peak exercise heart rate (p = 0.0003), percentage of maximal predicted heart rate (p = 0.0001), peak exercise double product (p = 0.048), therapy during exercise (p = 0.003), scintigraphic summed reversibility score (i.e., the summation of the segmental differences between stress and rest) (p = 0.014), as significant predictors of events. Three multivariate models were built, with clinical variables (Model 1, chi square 15.97), ergometric variables (Model 2, chi square 19.66), and with scintigraphic variables added to clinical/ergometric variables (Model 3, chi square 31.13). The scintigraphic variable selected in the model as significant predictor of events was the summed reversibility score (p = 0.008). CONCLUSIONS: Exercise sestamibi SPECT scintigraphy provides optimal prognostic information after clinical and ergometric parameters in patients with previous bypass surgery.

[Echocardiography or stress scintigraphy with dipyridamole for the stratification of risk after acute myocardial infarction?]. / Ecocardiografia o scintigrafia da stress con dipiridamolo per la stratificazione del rischio dopo infarto miocardico acuto?

UNLABELLED: Increased risk of subsequent cardiac events after an acute infarction can be identified through dipyridamole infusion. It remains to be determined whether echocardiographic or scintigraphic imaging modes are equivalent. The aim of our study was to compare the prognostic information obtained early after an acute uncomplicated myocardial infarction through high-dose dipyridamole coupled with echocardiography or scintigraphy via Tc 99m sestamibi SPECT imaging. METHODS AND RESULTS: Fifty-one patients underwent simultaneous dipyridamole stress echocardiography and scintigraphy at a mean +/- SD of 12 +/- 3 days after admission for acute uncomplicated myocardial infarction. A subgroup of 44 patients performed exercise testing according to maximal symptom limited protocol. All patients were followed prospectively for 346 +/- 273 days (range 11-959). Cardiac events occurred in 20 patients (39%), and 1 death, 2 myocardial reinfarctions and 17 cases of unstable angina were recorded. Univariate predictors of cardiac events were: positive dipyridamole echo (p < 0.001), ischemia in the infarct zone or in remote zones by echo (p < 0.001), ejection fraction < 40% (p = 0.042) and positive exercise testing (p = 0.003). Risk was best predicted by multivariate Cox analysis on the basis of 1) ischemia in remote zones by dipyridamole echo (p < 0.001) and 2) ischemia in the infarct zone by dipyridamole echo (p = 0.003), blood pressure at peak exercise < 150 mmHg (p = 0.010) and non-Q wave infarction (p = 0.003). CONCLUSIONS: Echocardiographic imaging during dipyridamole infusion is superior to sestamibi scintigraphy for predicting events after uncomplicated myocardial infarction.

[Combined use of bicycle ergometry test and echo-dipyridamole in stratification of risk after thrombolysed myocardial infarct]. / Uso combinato di test al cicloergometro ed eco-dipiridamolo per la stratificazione del rischio dopo infarto miocardico trombolisato.

AIM: Verify the value of the combined use of Dipyridamole Stress Echocardiography (DSE) and Exercise Testing (ET) for predicting cardiac events after Thrombolysed Myocardial Infarction (TMI). STUDY DESIGN: Prospective, with a medium follow-up of 221 days (range 30-446). CLINICAL SETTINGS: Coronary Care Unit with Cardiology Service. PATIENTS: 32 consecutive patients, 24 men and 8 women, mean age 61 years (range 39-72) with acute myocardial infarction. INTERVENTIONS: Systemic thrombolysis with PTPA. DSE and ET in therapeutic wash out 12 +/- 3 days after admission to the Coronary Care Unit. RESULTS: 9 patients had positive ET, 18 patients had negative ET, 5 patients did not perform ET. 19 patients had positive DSE, 13 patients had negative DSE. Patients with positive DSE had in 6 cases (group 1) WMA remote from the infarction area (WMAR), in 13 cases (group 2) WMA appeared in the infarct related area. Cardiac events occurred in 15 patients: 1 cardiovascular death, 1 myocardial re-infarction, 13 cases of unstable angina. 2 patients with negative DSE had cardiac events. All patients in group 1 had events, 1 patient with a previous positive ET, 3 patients with previous negative ET. 2 patients in this group didn't perform ET. 7 patients in group 2 had cardiac events, in all cases with a previous positive ET. 1 single patient in this group with negative ET had events. CONCLUSIONS: 1) Patients without WMA at DSE are at low risk for cardiac events after thrombolysed myocardial infarction. 2) Presence of WMAR appears to be associated with a higher risk, whatever the result of ET may be. 3) Patients without WMAR can be further stratified by ET in therapeutic wash out. High risk patients seem to be those with positive DSE and positive ET. 4) Combined use of DSE and ET seem to allow optimal risk stratification after thrombolysed myocardial infarction.

Usefulness of 99mTc-MIBI stress myocardial SPECT bull's-eye quantification in coronary artery disease.

99mTc-methoxy-isobutyl isonitrile (MIBI) myocardial SPECT quantification performed using a Bull's-eye polar map, was evaluated and compared with visual analysis in 120 patients with proven or suspected CAD. The study series comprised 106 men and 14 women, age 37-75 years (mean 51 +/- 6), 68 of whom had had a prior myocardial infarction. Coronary angiography was taken as the gold standard: one-vessel disease was present in 24 patients, two-vessel disease in 39, and three-vessel disease in 44, whereas no significant stenosis was documented in 13 cases. Forty age-matched subjects (26 men, 14 women), with less than a 5% chance of having CAD, were enrolled to establish the normal database for males and females. ROC analysis was used to calculate the optimal thresholds for the definition of the disease extension in each vascular territory of the Bull's-eye polar map: 10% for LAD, 8% for LCX, and 20% for RCA territory. The sensitivity/specificity ratio of the scintigraphy was: 75/82% with the visual and 78/74% with the quantitative analysis for LAD; 60/90% with visual and 72/64% with visual and 70/62% with quantitative analysis for RCA territory. The sensitivity/specificity ratios for the CAD diagnosis were similar with the visual and the Bull's-eye analysis in 92/61% and 93/61% respectively. Bull's-eye analysis agreed with visual analysis in 296/360 vessels. Two and three-vessel disease were most frequently observed using the Bull's-eye approach.(ABSTRACT TRUNCATED AT 250 WORDS)

[Trans-placental passage of amiodarone: electrocardiographic evidence and pharmacological findings in a newborn infant]. / Passaggio trans-placentare dell'Amiodarone: evidenza elettrocardiografica e documentazione farmacologica in un neonato.

Trans-placental passage of amiodarone has not yet been demonstrated, even if it has been suspected from the observation of some cases of congenital mixedema in babies born of amiodarone-treated women. A pregnant woman, suffering from recurrent episodes of resistant high frequency, 1:1 atrial tachycardia, with severe hypotension, was treated with oral amiodarone 200 mg daily during the last three months of pregnancy. The arrhythmia was satisfactorily controlled and pregnancy was carried on well. At birth, the baby was normal on physical examination and routine blood exams. Particularly, thyroid function was normal. After delivery, the plasma level of the drug and its electrocardiographic effects both in the mother and the newborn were determined. High pressure liquid chromatography (HPLC) method was used for the pharmacologic determinations and led to demonstrate the presence of amiodarone and one of its metabolites in the newborn plasma. Placental permeability for the metabolite resulted to be higher than for amiodarone, comparing mother versus newborn drug concentrations. Electrocardiographic changes due to amiodarone (i.e. lengthening of QT interval) were observed in both the ECGs of the mother and the newborn, but in the latter lenghthening of QT was much more evident. The authors briefly report another personal case of amiodarone-treatment during pregnancy and conclude, on the basis of their experience, that amiodarone can be used in pregnancy, but strictly in refractory, life-threatening arrhythmias and limitedly to the last three months.

[High-frequency electrostimulation of the atrium in therapy of atrial flutter in patients pre-treated with amiodarone]. / L'elettrostimolazione atriale ad alta frequenza nella terapia del flutter atriale in pazienti pre-trattati con amiodarone.

Twenty-four consecutive episodes of atrial flutter in 20 patients were treated with overdrive atrial pacing after a pre-treatment with oral Amiodarone. This technique was effective in interrupting the arrhythmia in 23 instances (95,8%). Normal sinus rhythm was restored in 22 cases: in 18 of then (75%) it appeared immediately at the end of stimulation and in 4 after a short intervening period of atrial fibrillation. In accordance with the experience of other authors, the combined pharmacological and electrical treatment provides a higher rate of conversion of atrial flutter into normal sinus rhythm and a lower rate of early relapses of the arrhythmia.

[Acute myocardial infarct as the first manifestation of acute myeloid leukemia. Description of an anatomo-clinical case]. / Infarto miocardico acuto come prima manifestazione di una leucemia mieloide acuta. Descrizione di un caso anatomo-clinico.

A case of a 46 year old man in whom acute myocardial infarction was the earliest outstanding clinical manifestation of an acute promyelocytic leukemia is reported. Reinfarction occurred a few days after, causing death of the patient. autopsy and histologic findings are reported and pathogenetic hypothesis are discussed. The Authors point out the role of an ipercoagulable state created by leukemia itself.

[Electrophysiological demonstration of more structures in the atrioventricular node (author's transl)]. / Evidenziazione elettrofisiologica di piu' strutture nel nodo atrioventricolare.

Three types of atrioventricular nodal conduction curves, relating A1A2 to H1H2, generated with atrial extrastimulus technique, are known. The first type is smooth, suggesting the homogeneous structure of A-V node. The second type, with abrupt increase in H1H2 response over a critical range of A1A2 coupling intervals, suggests the presence of fast and slow A-V nodal pathways. We have found in five patients the third tipe of A-V conduction curve, giving evidence of an intranodal final common pathway, distal to the fast and slow A-V nodal pathways. The thyrd type of curve enables us to know also some alectrophysiological properties of final common pathway. Indeed we have defined effective and functional refractory periods of fast, slow and final common pathways as far as we can in this type of curve. Paced heart rate variations and atropine medications have led the third type of A-V conduction curve to change into the second type in three cases, into first type in one case. These changes of A-V nodal conduction curves are related to different influence of cardiac cycle lenghts and autonomic nervous system on refractory periods and conduction velocity of the outlined intranodal structures.