Two Cases of Cardiac Arteriovenous Malformation Complicated by a Local Angioproliferative Process

Vascular malformations of the heart are extremely rare with only a few cases of the arteriovenous type of vascular malformation (AVM) reported. We investigated the pathology of two additional cases, which were complicated by the occurrence of a local vasoproliferative response of immature but benign vessels. We suppose that the mass forming effect of this vasoproliferative response, which has also been reported recently as a complication of congenital AVM elsewhere in the body, has significantly contributed to the onset of symptoms and ultimate death of both patients

Radiofrequency-induced thermotherapy of nasopharyngeal angiofibroma and immunohistochemical analysis of vessel proliferation: a case report

<p>Abstract</p> <p>Introduction</p> <p>Nasopharyngeal angiofibroma presents with symptoms of nasal obstruction and epistaxis. The treatment of choice is embolization followed by surgery.</p> <p>Case presentation</p> <p>A 52-year-old man underwent surgery for nasopharyngeal angiofibroma after adjuvant radiofrequency-induced thermotherapy. To the best of the authors' knowledge, this is the first case of angiofibroma with clinical follow-up after thermocoagulation therapy supported by quantitative, double immunohistochemistry. We found this case of angiofibroma to be of interest owing to the presentation of symptoms leading to biopsy, the pathohistological observations obtained with synchronous Ki67/cluster of differentiation 34 and Ki67/smooth muscle actin immunohistochemistry and high pericyte proliferation.</p> <p>Conclusion</p> <p>Coagulation of angiofibroma vessels followed by acquisition of a thick mantle of pericytes in a patient with a nasopharyngeal growth suggests that radiofrequency-induced thermotherapy could be a useful, palliative therapy for bleeding nasopharyngeal angiofibroma, supporting vessel maturation prior to surgical tumor removal.</p

Atypical MRI features in soft-tissue arteriovenous malformation: a novel imaging appearance with radiologic-pathologic correlation

BackgroundThe absence of a discrete mass, surrounding signal abnormality and solid enhancement are imaging features that have traditionally been used to differentiate soft-tissue arteriovenous malformations from vascular tumors on MRI. We have observed that these findings are not uncommon in arteriovenous malformations, which may lead to misdiagnosis or inappropriate treatment.ObjectiveTo estimate the frequency of atypical MRI features in soft-tissue arteriovenous malformations and assess their relationship to lesion size, location, tissue type involved and vascular architecture.Materials and methodsMedical records, MRI and histopathology were reviewed in consecutive patients with soft-tissue arteriovenous malformations in a multidisciplinary vascular anomalies clinic. Arteriovenous malformations were divided into those with and without atypical MRI findings (perilesional T2 signal abnormality, enhancement and/or a soft-tissue mass). Lesion location, size, tissue involved and vascular architecture were also compared between groups. Tissue stains were reviewed in available biopsy or resection specimens to assess relationships between MRI findings and histopathology.ResultsThirty patients with treatment-naïve arteriovenous malformations were included. Fifteen lesions demonstrated atypical MRI. There was no difference in age, gender, lesion size or involved body part between the groups. However, more than half of the atypical lesions demonstrated multicompartmental involvement, and tiny intralesional flow voids were more common in atypical arteriovenous malformations. Histopathology also differed in atypical cases, showing densely packed endothelial cells with connective tissue architectural distortion and edema.ConclusionArteriovenous malformations may exhibit features of a vascular tumor on MRI, particularly when multicompartmental and/or containing tiny internal vessels. These features are important to consider in suspected fast-flow vascular malformations and may have implications with respect to their treatment

Intraplaque hemorrhage in cardiac allograft vasculopathy.

Plaque hemorrhage, inflammation and microvessel density are key determinants of plaque vulnerability in native coronary atherosclerosis (ATS). This study investigates the role of intraplaque hemorrhage (IPH) and its relation with inflammation and microvessels in cardiac allograft vasculopathy (CAV) in posttransplanted patients. Seventy coronary plaques were obtained from 12 patients who died because of CAV. For each patient we collected both native heart and the allograft, at the time of transplantation and autopsy, respectively. Intralesion inflammation, microvessels and IPH were assessed semi-quantitatively. IPH was observed in 21/35 (60%) CAV lesions and in 8/35 (22.9%) native ATS plaques, with a strong association between fibrocellular lesions and IPH (p = 0.0142). Microvessels were detected in 26/35 (74.3%) of CAV lesions with perivascular leakage as sign of endothelial damage in 18/26 (69.2%). IPH was strongly associated with microvessels (p < 0.0001). Inflammation was present in 31/35 (88.6%) of CAV lesions. CAV IPH+ lesions were characterized by presence of both fresh and old hemorrhage in 12/21 (57.1%). IPH, associated with microvessel damage and inflammation, is an important feature of CAV. Fresh and old intralesion hemorrhage suggests ongoing remodeling processes promoting the lesion progression and vulnerability