[Treatment of subclavian artery stenosis with stents in patients previously treated with internal mammary left anterior descending artery bypass surgery]

We reported two cases of patients that underwent left internal mammary (LIMA)-coronary bypass graft and developed recurrent myocardial ischemia in the follow-up period caused by stenosis in the subclavian artery. The angiography showed retrograde flow from the left anterior descending artery to subclavian artery. After initial dilatation with a conventional angioplasty balloon catheter, we implanted Palmaz-Schatz Stents, achieving an excellent final result. Our finding suggest that Stent implantation is a safe and effective procedure, and provides an alternative to other forms of revascularization for the treatment of this disorder.

[Intermittent antero-medial divisional block in patients with coronary disease]

We report the case of a 69 year-old male who developed congestive heart failure functional class IV (NYHA). The admission electrocardiogram (EKG) revealed sinus rhythm, PR interval of 240 ms, QRS interval of 110 ms, the QRS vector of 0 degree, Q waves from V1 to V6, tall R waves from V1 to V4 that decreased to V5 and V6. The vectocardiogram had anteriorization of the electrical forces of QRS, with vector half area in the horizontal plane at +60 degrees. After two years the patient had a myocardial infarction, the EKG at the admission had the same pattern and after two days developed important changes: enlargement of QRS interval with length of 160 ms, QRS vector of +100 degrees, R waves at D2, D3 e AVF that increase from D2 to D3, QS at D1, AVL, AVR and V1, rS at V2 and V3, R wave is notched and thickened+ at V5 and V6, that return to the initial pattern after one day. The patient progressed to death in the eighth day after infarction. This case reported a intermitent pattern of EKG that is an uncontestable proof to the existence of the left middle fascicular block.

[Magnetic resonance imaging in chronic Chagas cardiopathy. Correlation with endomyocardial biopsy findings]

PURPOSE

To study the correlation between magnetic resonance imaging of the heart and right ventricle endomyocardial biopsy results in chronic Chagas' heart disease.

METHODS

Ten patients with Chagas' disease, mean age 47 +/- 7 years, all males, in congestive heart failure with New York Heart Association class II (2 patients), III (6) and IV (2) were studied. Mean left ventricular ejection fraction was at echocardiogram 36 +/- 6%. The patients were submitted to right ventricular endomyocardial biopsy and magnetic resonance imaging of the heart. The results of this group were compared with a control group of patients with idiopathic dilated cardiomyopathy, with mean age of 46 +/- 10 years and left ventricular ejection fraction of 30 +/- 4%, in heart failure with functional class II (1 patient), III (5) and IV (1).

RESULTS

All patients with Chagas' heart disease presented an increase in magnetic ressonance imaging signal of the heart after gadolinium use. The septal signal intensity changed from 0.87 +/- 0.06 to 1.54 +/- 0.16 (p < 0.001). In the control group the mean septal signal intensity was 0.93 +/- 0.07 before and 0.89 +/- 0.06 after the gadolinium (p = ns). Eight patients of the Chagas' disease group had biopsy proven myocarditis and two had borderline myocarditis. However, only one patient of the control group had diagnosis of borderline myocarditis.

CONCLUSION

Myocarditis is frequently found in Chagas' heart disease patients and who unlike controls present a significant increase in myocardial signal intensity after gadolinium infusion. The magnetic resonance imaging of the heart seems a promising alternative method for the diagnosis of an inflammatory process in Chagas' heart disease.

[Evaluation of chronic morphological changes in the latissimus dorsi, after cardiomyoplasty, with magnetic resonance]

PURPOSE

Long term clinical and hemodynamic benefits of dynamic cardiomyoplasty (DC) have been reported. However, no information is available about long-term morphological changes in the wrapped latissimus dorsi (LD) muscle in humans.

METHODS

The latissimus dorsi muscle flap was evaluated by magnetic resonance imaging (MRI) in 5 patients submitted to DC for treatment of severe dilated cardiomyopathy. All patients were studied from 24 to 52 months after the surgical procedure at the time of the cardiomyostimulator replacement. In the interim, LD was stimulated with burst of 6 pulses (burst duration 185 msec, burst freq 30Hz) synchronized to every cardiac contraction with a maximum of 100 LD contractions/min. Images were acquired on a GE Sigma 1.5 T system (TE = 25ms, TR = R- Rx2, slice thickness 8mm).

RESULTS

The thickness of was 7.6 +/- 0.8mm. In addition, the signal intensity of the LD was compared with that of thoracic skeletal muscle and was found to be increased (2.19 +/- 0.42). The signal intensity was similar to that of subcutaneous fat in those images.

CONCLUSION

Morphologic changes in the wrapped LD muscle consistent with fatty degeneration occur after DC and can be detected by MRI. Further studies will be necessary to demonstrate the clinical significance of such LD muscle flap changes.