Changes in left ventricle myocardial volume during stress test using cadmium-zinc-telluride cardiac imaging: Implications in coronary artery disease

BACKGROUND

Cadmium-zinc-telluride (CZT) SPECT allows the estimation of left ventricle myocardial volume (LVMV). We tested the clinical relevance of rest-stress LVMV changes (Δ LVMV) in detecting coronary artery disease (CAD, coronary stenosis > 70%), using CZT-SPECT.

METHODS

We prospectively enrolled 512 consecutive patients with known or suspected CAD (mean age: 70.3 ± 9.2 years, 72% male) for stress-rest myocardial perfusion imaging (MPI, single-day stress-rest protocol). We quantified summed stress scores (SSS), summed rest scores, and summed difference scores, together with LVMV and ejection fraction (EF) after stress and at rest. All patients underwent coronary angiography within 30 days.

RESULTS

Two hundred seventy-two patients had CAD at coronary angiography. ΔLVMV ≤ 5 mL, corresponding to 6% of change from rest LVMV, was the best predictor of CAD (AUC = 0.831, 79% sensitivity, 82% specificity), irrespective of the stress protocol (dipyridamole or exercise stress) and independently of MPI-SSS, LV EF, and clinical history (P = 0.004). Integrated discrimination improvement (IDI) and net reclassification improvement (NRI) were significant for the addition of ΔLVMV ≤ 5 mL (IDI = 6.1%, P < 0.0001; NRI = 29.7%, P = 0.02) to MPI-SSS, whereas the other parameters were not.

CONCLUSIONS

The evaluation of ΔLVMV using CZT-SPECT can improve the diagnostic accuracy in predicting the presence of CAD when added to conventional MPI.

Head-to-head comparison of a CZT-based all-purpose SPECT camera and a dedicated CZT cardiac device for myocardial perfusion and functional analysis

PURPOSE

To compare the outputs of a novel all-purpose SPECT camera equipped with CZT detectors (Discovery NM/CT 670) with the state-of-the-art represented by a dedicated CZT (Alcyone, Discovery 530c) cardiac camera in patients submitted to myocardial perfusion imaging (MPI).

METHODS

We included 19 patients that underwent sequential low-dose 99mTc-tetrofosmin (148-185 MBq during stress and 296-370 MBq at rest) MPI with Alcyone and Discovery 670 cameras. Quantitative (% tracer's uptake) and semi-quantitative analyses of perfusion data were performed for each scan. Moreover, major left ventricular (LV) functional and structural parameters were derived from each camera and compared.

RESULTS

The two cameras showed excellent correlation for segmental myocardial % uptake at stress (R = 0.90; P < 0.001) and at rest (R = 0.88; P < 0.001) with narrow Bland-Altman limits of agreement. The level of diagnostic agreement of Discovery 670 and Alcyone cameras regarding perfusion analysis was excellent (Cohen's κ 0.85). Similarly, the two cameras showed excellent correlation in the evaluation of LV ejection fraction (R = 0.95), peak filling rate (R = 0.97), and mass (R = 0.98).

CONCLUSIONS

Our preliminary results suggest that MPI with an all-purpose Discovery 670 CZT-SPECT camera is feasible, comparing well with the current state-of-the-art technology.

Cardio-pulmonary involvement in pulmonary arterial hypertension: A perfusion and innervation scintigraphic evaluation

BACKGROUND

Pulmonary arterial hypertension (PAH) is characterized by the right ventricle (RV) remodeling and pulmonary endothelial dysfunction. We studied cardiac perfusion and innervation in PAH with a cadmium-zinc-telluride (CZT) scanner and lung uptake impairment of 123I-metaiodobenzylguanidine (123I-MIBG).

METHODS

In 13 patients with newly diagnosed PAH and 11 dilated cardiomyopathies (DCM, for comparative purposes), we assessed early and delayed 123I-MIBG uptake ratios of lung-to-mediastinum (L/M) and heart-to-mediastinum (H/M) on anterior planar images. A quantitative myocardial innervation with 123I-MIBG and perfusion with 99mTc-tetrofosmin using CZT-SPECT was performed. All patients underwent right heart catheterization.

RESULTS

Early and delayed L/M ratios in PAH were lower than DCM (1.47 ± 0.14 vs 1.98 ± 0.11 and 1.40 ± 0.13 vs 1.83 ± 0.09; P < .001), while early and delayed H/M were impaired but not different (1.73 ± 0.20 vs 1.65 ± 0.18 and 1.73 ± 0.27 vs 1.58 ± 0.19). RV perfusion and early innervation were significantly higher in PAH compared to DCM (68.4 ± 13.4 vs 28.6 ± 4.1 and 58.8 ± 9.3 vs 27 ± 2.2; P < .001); delayed RV innervation was not evaluable. RV/LV perfusion and innervation ratios were significantly related (R = 0.74; P < .0001) and had a significant correlation with clinical, hemodynamic, and morpho-functional parameters, including L/M ratios.

CONCLUSION

Cardio-pulmonary scintigraphy through a perfusion and innervation study is feasible and may identify pulmonary vascular and RV remodeling, as in PAH.

[Short-stay surgery of inguino-crural hernia]

BACKGROUND

To evaluate the hospital stay, morbidity, and patients' compliance for short stay inguinal hernia repair.

METHODS

Retrospective analysis of 669 patients (594 men and 75 women) who underwent short stay inguinal hernia repair (706 inguinal and 45 femoral repairs) at the Institute of General Surgery, University of Ferrara. Mean age was 60.7 years (range, 18-84 years). The anesthesia was: loco-regional in 495 patients (74%) and general or epidural in 174 (26%).

RESULTS

Mean hospital stay was 1.2 days. Postoperative complications were: three scrotal hematomas, two ischemic orchitis, three prosthetic infections, one local anesthetic intolerance, and three high fever. Eighty-five percent of patients were satisfied of the surgical procedure in short hospital stay. Mean follow-up was 36 months.

CONCLUSIONS

Short hospital stay in inguinal hernia repair is safe, effective, and widely accepted by patients.

Alternative saphenous vein sparing surgery for future grafting

OBJECTIVE

Evaluation of long saphenous vein sparing surgical procedures alternative to high ligation and distal stab avulsion, in terms of effectiveness and suitability for eventual by-pass surgery.

EXPERIMENTAL DESIGN

Prospective evaluation of 125 operations for primary varicose veins, 52 external valve-plasties of the sapheno-femoral junction (EV-SFJ) (42 performed using the hand sewing technique and 10 using the Veno-cuff device), mean follow-up 45 months, and 73 hemodynamic correction of varicose veins (French acronyms: CHIVA), mean follow-up 30 months.

SETTING

Department of General Surgery, University of Ferrara. Institutional practice, one-day surgery.

PATIENTS

Patients were selected using clinical, Doppler cw, and duplex scanning evaluations. Patients with early varices due to sapheno-femoral reflux with duplex scanning evidence of mobile valve leaflets underwent EV-SFJ. The other patients were operated on using the hemodynamic correction technique. Both groups underwent preoperative ambulatory venous pressure (AVP) and light reflection rheography-refilling time (LRR-RT) measurements.

INTERVENTIONS

EV-SFJ restores valve function correcting vein wall dilitation by applying an external prosthesis. CHIVA consists of selected ligatures of the superficial veins that allow superficial blood aspiration in the deep veins through the perforators.

MEASURES

The outcome was evaluated with clinical and ultrasonographic examinations, AVP and LRR-RT measurements.

RESULTS

Long saphenous vein patency registered after EV-SFJ and CHIVA was 94.2% and 90.4%, respectively. Both treatments preserve the drainage function in the saphenous system. Varicose veins recurrence percentage rate was 9.6% and 10.9%, respectively.

CONCLUSIONS

Following the proposed selection criteria, these two alternative procedures seem to be more effective in varices treatment than high ligation and have the advantage of preserving saphenous veins suitable for eventual by-pass surgery.

[Laparoscopic treatment of Mirizzi's syndrome]

The Mirizzi syndrome is an unusual benign obstructive jaundice due to extrinsic mechanical compression of the common hepatic duct by gallstone impacted within the neck or cystic duct of the gallbladder. This syndrome is described either as an acute form due only to extrinsic compression of the common bile duct (type I) or as a chronic form resulting in an erosive cholecysto-choledochal fistula (type II). Up to date, the syndrome remains a clinically and surgically challenging problem. The anatomic basic of the syndrome (an anomalous relationship between the cystic duct and the common hepatic duct) when associated with inflammation and interbiliary fistula predisposes to a critical situation to be clearly detected and contributes to technical difficulties when surgical management is performed. The operative diagnosis of Mirizzi syndrome remains elusive and requires careful scrutiny of the biliary tract imaging to recognize the diseased duct system and to facilitate the following operative procedures. The surgical treatment requires a skill and careful operative dissection of the duct system, cholecystectomy and a safe biliary exploration and stone clearance, avoiding any iatrogenic damage to common hepatic duct. Laparotomy is commonly advocated as the safer approach to the diseased biliary tract and it is still employed by most authors. The laparoscopic surgery has not yet entered as the first-choice procedure for this syndrome due to jaundice and acute inflammation considered by some as contraindication to mini-invasive treatment. This paper describes successful surgical management by laparoscopic techniques in two patients affected by Mirizzi type I and type II syndrome treated by cholecystectomy alone and cholecystectomy with choledochal fistula flap repair, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)