Afksendiyos Kalangos

Inhaled Nitric Oxide Versus Aerosolized Iloprost in Secondary Pulmonary Hypertension in Children With Congenital Heart Disease Vasodilator Capacity and Cellular Mechanisms

Background —Inhaled nitric oxide (iNO) has been used to assess the vasodilator capacity of the pulmonary vascular bed in children with congenital heart disease and elevated pulmonary vascular resistance. Inhaled iloprost is a pulmonary vasodilator for the long-term treatment of pulmonary hypertension (PHT). Because these 2 vasodilators act through different pathways (release of cGMP or cAMP, respectively), we compared the pulmonary vasodilator capacity of each. Methods and Results —A total of 15 children with congenital heart disease and PHT who had elevated pulmonary vascular resistance (preoperative, n=10; immediately postoperative, n=5) were first given 20 ppm of iNO for 10 minutes; then, after baseline values were reached again, they were given aerosolized iloprost at 25 ng · kg−1 · min−1 for another 10 minutes. Finally, iNO and iloprost were given simultaneously for 10 minutes. With iNO, the pulmonary vascular resistance and systemic vascular resistance ratio decreased from 0.48±0.38 to 0.27±0.16 (P <0.001). Similarly, iloprost decreased the ratio from 0.49±0.38 to 0.26±0.11 (P <0.05). The combination had no additional effect on the resistance ratio. Plasma cGMP increased from 17.6±11.9 to 34.7±21.4 nmol/L during iNO (P <0.01), and plasma cAMP increased from 55.7±22.9 to 65.1±21.2 nmol/L during iloprost inhalation (P <0.05). Conclusions —In children with PHT and congenital heart disease, both iNO and aerosolized iloprost are equally effective in selectively lowering pulmonary vascular resistance through an increase in cGMP or cAMP, respectively. However, the combination of both vasodilators failed to prove more potent than either substance alone. Aerosolized iloprost might be an alternative to iNO for early testing of vascular reactivity and for the postoperative treatment of acute PHT.

Treatment of a persistent postoperative chylothorax with somatostatin

Chylothorax is a rare but potentially serious complication of pediatric cardiac operations. We report the case of a 4-month-old boy who underwent a Senning procedure for correction of D-transposition of the great vessels. A persistent postoperative chylothorax developed, necessitating continuous drainage, despite conservative treatment over 3 weeks. Thereafter, continuous somatostatin infusion for 14 days led to the reduction and finally cessation of chyle production. This treatment allowed early enteral feeding and avoided further surgical intervention.

Impending Paradoxical Embolism: Systematic Review of Prognostic Factors and Treatment

BACKGROUND Little is known about the optimal management of impending paradoxical embolism (IPDE), a biatrial thromboembolus caught in transit across a patent foramen ovale. Our aim was to review observational studies on this subject to identify prognostic factors and to compare mortality and systemic embolism between treatments. METHODS Systematic literature searches in Medline, Embase, and Cochrane Library identified 154 studies (174 patients). The primary end point was 30-day mortality. The secondary end point was systemic embolism during treatment. RESULTS Thirty-day mortality was 18.4%. On univariate analysis, age (64+/-13.9 vs 56.7+/-16.5; P = .01), coma (12.9% vs 2.2%; P = .02), and systemic embolism (71.9% vs 51.4%; P = .048) at presentation were significantly increased among nonsurvivors. Surgical thromboembolectomy had lower mortality than other treatment groups (10.6%; P = .04). In multivariable models, no prognostic factor was a significant independent predictor of mortality. Surgically treated patients had nonsignificantly reduced mortality (odds ratio [OR], 0.65 [0.24-1.72]; P = .65) and thrombolysis-treated patients had increased mortality (OR, 1.62 [0.43-5.97]; P = .47). However, systemic embolism during treatment and combined mortality and systemic embolism was decreased in the surgery group (OR, 0.13 [0.03-0.67]; P = .02 and OR, 0.26 [0.11-0.60]; P = .001). CONCLUSIONS This review attempts to help guide what to do in IPDE, despite severe limitations of the methods. Surgical thromboembolectomy showed a nonsignificant trend toward improved survival, significantly reduced systemic embolism, and composite of mortality and systemic embolism, compared with anticoagulation alone. Thrombolysis, on the other hand, had the opposite effect, although not significantly.

Degradation and healing characteristics of small-diameter poly(epsilon-caprolactone) vascular grafts in the rat systemic arterial circulation.

Background— Long-term patency of conventional synthetic grafts is unsatisfactory below a 6-mm internal diameter. Poly(&egr;-caprolactone) (PCL) is a promising biodegradable polymer with a longer degradation time. We aimed to evaluate in vivo healing and degradation characteristics of small-diameter vascular grafts made of PCL nanofibers compared with expanded polytetrafluoroethylene (ePTFE) grafts. Methods and Results— We prepared 2-mm–internal diameter grafts by electrospinning using PCL (Mn=80 000 g/mol). Either PCL (n=15) or ePTFE (n=15) grafts were implanted into 30 rats. Rats were followed up for 24 weeks. At the conclusion of the follow-up period, patency and structural integrity were evaluated by digital subtraction angiography. The abdominal aorta, including the graft, was harvested and investigated under light microscopy. Endothelial coverage, neointima formation, and transmural cellular ingrowth were measured by computed histomorphometry. All animals survived until the end of follow-up, and all grafts were patent in both groups. Digital subtraction angiography revealed no stenosis in the PCL group but stenotic lesions in 1 graft at 18 weeks (40%) and in another graft at 24 weeks (50%) in the ePTFE group. None of the grafts showed aneurysmal dilatation. Endothelial coverage was significantly better in the PCL group. Neointimal formation was comparable between the 2 groups. Macrophage and fibroblast ingrowth with extracellular matrix formation and neoangiogenesis were better in the PCL group. After 12 weeks, foci of chondroid metaplasia located in the neointima of PCL grafts were observed in all samples. Conclusions— Small-diameter PCL grafts represent a promising alternative for the future because of their better healing characteristics compared with ePTFE grafts. Faster endothelialization and extracellular matrix formation, accompanied by degradation of graft fibers, seem to be the major advantages. Further evaluation of degradation and graft healing characteristics may potentially lead to the clinical use of such grafts for revascularization procedures.

Successful Management of a Postinfarction Left Ventricular Rupture Using a Sutureless Technique With Concomitant Myocardial Revascularization

Abstract We present a case of left ventricular (LV) rupture that occurred on the second day after inferolateral myocardial infarction (MI). An aggressive diagnostic approach with rapid coronary angiography prior to surgical repair provides a benefit characterized postoperatively by complete recovery of myocardial contractility in the akinetic infarcted area. We believe that coronary artery disease associated with subacute ventricular rupture may, in fact, be better investigated and simultaneously treated under a protocol of early surgical repair.

Floating thrombus in the ascending aorta: A rare cause of peripheral emboli

The ascending aorta may be the site of origin of systemic embolization in some cases that do not have an identifiable source. We report a case in which a free-floating thrombus in the noncoronary sinus of Valsalva was detected by transesophageal echocardiography as a source of left axillary artery embolism. After removal of this pedunculated thrombus of unknown cause, which was attached on a macroscopically and histologically normal aortic wall, the patient made an uneventful recovery.

Original ResearchVenous ThromboembolismImpending Paradoxical Embolism: Systematic Review of Prognostic Factors and Treatment

BACKGROUND Little is known about the optimal management of impending paradoxical embolism (IPDE), a biatrial thromboembolus caught in transit across a patent foramen ovale. Our aim was to review observational studies on this subject to identify prognostic factors and to compare mortality and systemic embolism between treatments. METHODS Systematic literature searches in Medline, Embase, and Cochrane Library identified 154 studies (174 patients). The primary end point was 30-day mortality. The secondary end point was systemic embolism during treatment. RESULTS Thirty-day mortality was 18.4%. On univariate analysis, age (64+/-13.9 vs 56.7+/-16.5; P = .01), coma (12.9% vs 2.2%; P = .02), and systemic embolism (71.9% vs 51.4%; P = .048) at presentation were significantly increased among nonsurvivors. Surgical thromboembolectomy had lower mortality than other treatment groups (10.6%; P = .04). In multivariable models, no prognostic factor was a significant independent predictor of mortality. Surgically treated patients had nonsignificantly reduced mortality (odds ratio [OR], 0.65 [0.24-1.72]; P = .65) and thrombolysis-treated patients had increased mortality (OR, 1.62 [0.43-5.97]; P = .47). However, systemic embolism during treatment and combined mortality and systemic embolism was decreased in the surgery group (OR, 0.13 [0.03-0.67]; P = .02 and OR, 0.26 [0.11-0.60]; P = .001). CONCLUSIONS This review attempts to help guide what to do in IPDE, despite severe limitations of the methods. Surgical thromboembolectomy showed a nonsignificant trend toward improved survival, significantly reduced systemic embolism, and composite of mortality and systemic embolism, compared with anticoagulation alone. Thrombolysis, on the other hand, had the opposite effect, although not significantly.

Left atrial myxoma presenting with myocardial infarction: Case report and review of the literature

Coronary artery embolization is an extremely rare and potentially lethal complication of atrial myxomas. We present a case report and a literature review of this clinical association. A 53-year-old woman presented with an acute infero-lateral myocardial infarction. Coronary angiography performed 1 h after the onset of pain disclosed an abrupt stop and multiple embolization of the peripheral right coronary artery (RCA). A transthoracic echocardiographic study revealed the presence in the left atrium of an echogenic, mobile mass, compatible with myxoma. The tumour was successfully removed surgically 2 weeks later and the patient is doing well one year post operatively.

Paclitaxel-eluting biodegradable synthetic vascular prostheses: a step towards reduction of neointima formation?

Background— Clinical small-caliber vascular prostheses are unsatisfactory. Reasons for failure are early thrombosis and late intimal hyperplasia. We thus prepared biodegradable small-caliber vascular prostheses using electrospun polycaprolactone (PCL) with slow-releasing paclitaxel (PTX), an antiproliferative drug. Methods and Results— PCL solutions containing PTX were used to prepare nonwoven nanofibre-based 2-mm ID prostheses. Mechanical morphological properties and drug loading, distribution, and release were studied in vitro. Infrarenal abdominal aortic replacement was carried out with nondrug-loaded and drug-loaded prostheses in 18 rats and followed for 6 months. Patency, stenosis, tissue reaction, and drug effect on endothelialization, vascular remodeling, and neointima formation were studied in vivo. In vitro prostheses showed controlled morphology mimicking extracellular matrix with mechanical properties similar to those of native vessels. PTX-loaded grafts with suitable mechanical properties and controlled drug-release were obtained by factorial design. In vivo, both groups showed 100% patency, no stenosis, and no aneurysmal dilatation. Endothelial coverage and cell ingrowth were significantly reduced at 3 weeks and delayed at 12 and 24 weeks in PTX grafts, but as envisioned, neointima formation was significantly reduced in these grafts at 12 weeks and delayed at 6 months. Conclusions— Biodegradable, electrospun, nanofibre, polycaprolactone prostheses are promising because in vitro they maintain their mechanical properties (regardless of PTX loading), and in vivo show good patency, reendothelialize, and remodel with autologous cells. PTX loading delays endothelialization and cellular ingrowth. Conversely, it reduces neointima formation until the end point of our study and thus may be an interesting option for small caliber vascular grafts.

Ruptured mediastinal bronchial artery aneurysm: A dilemma of diagnosis and therapeutic approach

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