Effects of short-term carvedilol on the cardiac sympathetic activity assessed by 123I-MIBG scintigraphy.

Background: Autonomic alterations in heart failure are associated with an increase in morbimortality. Several noninvasive methods have been employed to evaluate the sympathetic function, including the Meta-Iodobenzylguanidine (123I-MIBG) scintigraphy imaging of the heart.

Objective: to evaluate the cardiac sympathetic activity through 123I-MIBG scintigraphy, before and after three months of carvedilol therapy in patients with heart failure and left ventricular ejection fraction (LVEF) < 45%.

Prevalence of induced ischemia by mental distress.

Background: The myocardial radionuclide imaging with mental distress seems to induce ischemia through a particular physiopathology when compared to radionuclide imaging with physical or pharmacological distress.

Objective: To assess the prevalence of induced myocardial ischemia by mental distress in patients with thoracic pain and radionuclide imaging with normal conventional distress, with 99mTc-Sestamibi.

Methods: Twenty-two patients were admitted with thoracic pain at emergency or were referred to the nuclear medicine service of our institution, where myocardial radionuclide imaging of distress or rest without ischemic alterations was carried out.

Radionuclide imaging of myocardium with mental stress in the investigation of thoracic pain.

Thoracic pain is a common symptom in emergency services, and stress radionuclide imaging represents one of the phases of risk stratification in these individuals. However, a group of patients with negative functional exams after physical or pharmacological stress develops myocardial ischemia during this psychological stress. Alterations in vascular tonus as a response to endogenous mechanisms are the physiopathologic basis for such alterations.

Use of resting myocardial scintigraphy during chest pain to exclude diagnosis of acute myocardial infarction.

Background: Images of myocardial perfusion taken during an episode of chest pain have been used for patients in the emergency department.

Objective: To evaluate the operating characteristics of 99mTc-Tetrofosmin scintigraphy during an episode of chest pain to exclude the diagnosis of acute myocardial infarction.

Methods: One hundred and eight patients admitted with chest pain, or up to four hours after the end of symptoms and nondiagnostic electrocardiogram, underwent resting scintigraphy and measurement of troponin I concentrations.

Medium term prognostic value of stress myocardial perfusion scintigraphy in a chest pain unit.

Objective: To evaluate the prognostic value of stress myocardial perfusion scintigraphy (MPS) applied to patients with suspected acute coronary syndrome (ACS).

Methods: Retrospective study. Patients with suspected acute coronary syndrome (ACS) admitted into the chest pain unit (CPU) from December 2002 to April 2004, after exclusion of acute myocardial infarction (AMI) and high risk unstable angina they underwent stress MPS.