Transarterial and transvenous embolization for cavernous sinus dural arteriovenous fistulae

We report on the safety and efficacy of trans-arterial and transvenous Onyx embolization in the treatment of dural arteriovenous fistulae (DAVFs) of the cavernous sinus. We reviewed the findings from a retrospectively database for 22 patients with cavernous sinus DAVFs who were treated with either transarterial Onyx embolization alone (n = 8) or transarterial and transvenous Onyx embolization (n = 14) over a four year period. The mean follow-up period after endovascular treatment was 21.6 months (range 3-42 mths). Total number of embolizations was 27 for 22 patients. Two patients were treated transvenously after transarterial embolization. All 22 patients (100%) experienced improvement of their clinical symptoms. All 22 patients (100%) experienced total obliteration of their DAVFs, as documented by angiography performed at a mean follow-up of 5.8 months after the last treatment. No patient experienced a recurrence of symptoms after angiography showed DAVF obliteration. One patient exhibited temporary deterioration of ocular symptoms secondary to venous hypertension after near total obliteration; one had transient V cranial nerve deficit related to transarterial embolization, and two patients exhibited transient III and VI cranial nerve weakness related to transvenous embolization. Two patients experienced recurrent symptoms after incomplete transarterial embolization and underwent transvenous embolization at three and four months. Both patients achieved clinical and angiographic cures. Transarterial and transvenous embolization with Onyx, whenever possible, proved to be a safe and effective management for patients with cavernous sinus DAVFs.

Role of neurocrine somatostatin on sphincter of Oddi contractility and intestinal ischemia reperfusion-induced acute pancreatitis in macaques

BACKGROUND

Intestinal ischemia-reperfusion (IIR) is implicated in the pathogenesis of severe acute pancreatitis (SAP). This study investigates the impact of neurocrine somatostatin (SST) on the contraction of sphincter of Oddi (SO) during IIR.

METHODS

Intestinal ischemia-reperfusion model in macaques was induced by occluding the superior mesenteric artery. Pancreatitis was confirmed by pancreatic histology and serum levels of amylase and lipase. SST and its receptors (SSTRs) in SO were visualized by immunohistochemistry. Effects of SST on the contraction of the isolated SO were recorded in vitro.

KEY RESULTS

Inflammatory scores of the pancreas and serum levels of amylase or lipase in the macaques that underwent IIR were significantly higher than those in the control group. The frequency and amplitude of phasic contraction of the circular muscle in SO was increased by SST in a concentration-dependent manner. Compared with the control group, SST innervation or SSTR2 expression in SO of macaques treated with IIR was increased 5.2 fold or 5.6 fold respectively. Prophylactic infusion of SST before IIR significantly reduced SST immunoreactive fibers in SO as compared to those in the IIR group and remarkably alleviated the pathophysiologic changes due to IIR.

CONCLUSIONS & INFERENCES

Increased SST innervation in SO during the early phase of IIR associated with the contraction of circular muscle of SO, which might be one of the promoting factors associated with the development of SAP. Prevention of IIR or intervention of SO contraction after occurrence of acute pancreatitis might be beneficial for preventing SAP.

Clinical outcomes of ruptured and unruptured vertebral artery-posterior inferior cerebellar artery complex dissecting aneurysms after endovascular embolization

BACKGROUND AND PURPOSE

Surgical treatment of VA-PICA dissecting aneurysms is difficult and complication of LCNP is common. These lesions can be approached easily with endovascular technique, but complete obliteration can only be achieved in a small number of cases. Our aim was to report the clinical outcomes of VA-PICA dissecting aneurysms treated by endovascular embolization.

MATERIALS AND METHODS

Between 2001 and 2007, the authors treated 22 consecutive patients (15 men and 7 women; ranging in age from 12 to 59 years; mean age, 43 years) with VA-PICA dissecting aneurysms. Diagnosis of VA-PICA dissecting aneurysm was based on clinical, MR imaging, and cerebral angiography studies.

RESULTS

Of the 22 patients, 6 had unruptured aneurysms. One patient presented with headaches, whereas the remaining 5 patients showed brain stem ischemia. Four were treated with stent-only or stent-coil embolization, and 2 were treated with unilateral VA occlusion. Among 16 patients presenting with SAH, 10 were treated with stent-only or stent-coil embolization. The other 6 patients with SAH were treated by using unilateral endovascular VA occlusion. One patient could not return to his previous daily activities.

CONCLUSIONS

VA-PICA aneurysms are rare lesions associated with significant morbidity, and endovascular treatment strategies for these lesions were stent deployment with or without coil embolization and VA occlusion. Favorable clinical outcomes can be achieved with endovascular techniques.

A systematic comparison between collagen-induced arthritis and pristane-induced arthritis in Dark Agouti rats

OBJECTIVES

Both collagen-induced arthritis (CIA) and pristane-induced arthritis (PIA) are commonly used rat models of rheumatoid arthritis (RA). The aim of this study was systematically to compare the differences between CIA and PIA in Dark Agouti (DA) rats.

METHODS

The CIA was induced by immunising DA rats intradermally with collagen type (C) and PIA was induced by injecting subcutaneously with pristane. The arthritis was evaluated macroscopically and microscopically. Nitric oxide (NO) level of plasma was determined by Griess reaction method. Plasma autoimmune antibodies, including C specific IgG antibody (anti-C IgG), cyclic citrullinated peptide specific IgG antibody (anti-CCP IgG), IgM and IgG rheumatoid factors (IgM RF and IgG RF), were detected by the enzyme-linked immunosorbent assay.

RESULTS

The onset of PIA rats was earlier than that of CIA rats. The involved sites of PIA rats were mostly wrist/ankle and metacarpophalangeal/metatarsophalangeal (MCP/MTP) joints while those of CIA rats were primarily distal interphalangeal (DIP) joints. NO level of plasma was increased in PIA rats, as anti-C IgG, anti-CCP IgG, IgM RF and IgG RF levels of plasma were increased in CIA rats. The kidney hyaline casts were more frequent in CIA rats than in control rats, with 9/12 in PIA group, 8/8 in CIA, and 4/8 in control, respectively.

CONCLUSIONS

PIA mainly affected wrist/ankle joints and MCP/MTP joints, had more severe inflammation and hardly involved other organs; while CIA mostly influenced DIP joints, had more autoimmune antibodies in plasma, and always showed hyaline casts in kidney. These findings will be useful to select the animal model of RA.

Diversity of soil actinomycetes in yunnan, china

Since 1978, about 4,200 soil samples have been collected from 22 selected areas of various vegetational and climatic types throughout the province of Yunnan. Actinomycetes of 29 genera were isolated by the methods employed. The correlations between diversity and climate were grouped into tropical, subtropical plateau, cool temperate mountain, and snowy mountain types. Actinomycete populations of the first two types were more complex than were the other ones. Correlations between actinomycete diversity and vegetation were also attempted. Six types of vegetation were compared. The diversity of actinomycetes was greatest in soil samples of a primeval forest, with an average of 9.0 genera isolated, followed by secondary forest and vegetable farmland samples, with averages of 6.7 and 6.5 genera isolated, respectively. The upper limit for the occurrence of thermophilic actinomycetes is about 3,500 m above sea level in Yunnan. Psychrophilic actinomycetes were isolated at up to the same altitude. In addition, the drier and poorer the soil was and the cooler the climate was, the lower the count of actinomycetes was and the higher the percentage of streptomycetes observed was. The genus Streptomyces appears to be the most important in ecological function. It represents up to 90% of all soil actinomycete diversity in Yunnan and is likely an important characteristic of the soil actinomycete population.

Diversity of aquatic actinomycetes in lakes of the middle plateau, yunnan, china

A total of 749 sediment and water samples were collected from 12 lakes of the Middle Plateau of Yunnan from 1983 to 1993. The diversity and biological characteristics of the aquatic actinomycetes in these lakes were studied. Sixteen genera of actinomycetes were isolated from these samples. Micromonospores assumed a notable dominance (from 39 to 89%) in the actinomycete populations of these lake sediments. Streptomycetes were the second most abundant organisms. The diversity and counts of actinomycetes varied with the season. Thermophilic actinomycetes have a wide distribution in these lakes, but their counts were smaller. The cell wall compositions of certain Micromonospora and Streptomyces strains from an alkaline lake revealed an unusual combination of glycine and isomers of diaminopimelic acid. It seems that aquatic actinomycetes play a significant role in the decomposition of organic substances, including some toxic compounds such as phenol, in these lakes. It also appears that aquatic actinomycetes are one of the important resources for screening useful enzymes and metabolites.

Endovascular embolization for deep Basal Ganglia arteriovenous malformations

We report our experience with basal ganglia AVM embolization and clinical outcomes after embolization. We retrospectively evaluated consecutive 15 patients with AVMs in the basal ganglia with respect to the endovascular treatment of these lesions. Treatment consisted of embolization and radiosurgery in combination. The angiographic follow-up after the last management was 24-36 months (mean 27 months). Clinical follow-up monitoring (range, 24-120 months, mean 76 months) was measured by the Modified Rankin Scale (mRS). The 15 patients studied had a mean age of 25.1 years at diagnosis, and 33.3% were male. Intracranial hemorrhage (ICH) was the event leading to clinical detection in eight patients (53.3%), and 85.5% of these patients were left with hemiparesis. At presentation, eight (53.3%) patients bled a total of 11 times. Twenty-four embolization procedures (16 pedicles embolized) were performed in 15 patients with embolization as the adjunct to radiosurgery. There were three clinically significant complications. Excellent or good outcomes (mRS≤2) were observed in 13 (86.7%) patients. Unfavorable outcomes (mRS≤2) were 13.3% at follow-up, without mortality. Seven (46.7%) patients had complete AVM obliteration at follow-up. The risk of incurring a neurological deficit with basal ganglia AVM is high. Treatment of these patients is endovascular embolization with a combination of radiosurgery to prevent neurological injury from a spontaneous ICH.

Endovascular treatment accounts for a change in brain arteriovenous malformation natural history risk

This study estimated the risk and rates of intracranial hemorrhage (ICH) in patients harbor-ing brain arteriovenous malformation (BAVM) after endovascular embolization. One hundred and forty-four consecutive patients with BAVM treated with endovascular embolization between 1998 and 2003 were retrospectively reviewed. The risk of ICH subsequent to endovascular embolization was studied using Kaplan-Meier curves. We reviewed 144 patients with BAVM treated with endovascular embolization. Two hundred and sixty-nine procedures were performed, 69 were performed with silk sutures, 18 with coils, 137 with NBCA and 36 with Onyx18. Twenty-three (16.0%) patients were treated with additional gamma-knife radiosurgery and one (0.7%) with additional surgical AVM excision. Complete obliteration of BAVMs was achieved in 20 patients (13.9%). During a mean follow-up of 5.9 years for the ICH group and 6.9 years for the non-ICH group, hemorrhages occurred in 11 (17.7%) of the ICH patients and in nine (11%) of the non-ICH group (p>0.1). The annual risk of hemorrhage was 3.0% and 1.6%, respectively. In the multivariate regression model, the adjusted relative risk (RR) for hemorrhage at initial presentation was 1.6 (95% CI 1.2-3.2; p>0.1). Deep venous drainage, male sex, age or AVM size were not significantly associated with subsequent hemorrhage. ICH and non-ICH groups did not differ in progression to subsequent ICH after endovascular embolization (log-rank X (2) =1.339, p>0.1) in survival analyses. The overall annual hemorrhage risk for all patients after endovascular embolization was 2.1%. Endovascular embolization alone or combined with gamma-knife radiosurgery or surgical treatment are able to decrease ICH occurrence compared to abstention.

Periprocedural bleeding complications of brain AVM embolization with Onyx

The advent of Onyx has provided a new method for neurointerventional therapists to treat brain AVMs. Although some retrospective studies have reported complications for AVM embolization with Onyx, periprocedural bleeding complications with Onyx embolization have not yet been described in detail. The aim of this retrospective study was to analyze the factors of Onyx-related bleeding complications and to find a way to avoid and manage these complications.From January 2003, patients with AVMs recruited in our institution started to be treated by Onyx embolization. From January 2007 to July 2009, 143 consecutive interventions were performed in 126 patients using flow-independent microcatheters and Onyx as embolic agents. Seven patients encountered bleeding complications (5.4% per patients and 4.7% per procedures) during or after the endovascular procedures. Among them, five bleeding episodes occurred during procedures, the other two after procedures. Details of the seven patients' clinical presentations, imaging presentations, speculative reasons and management of these complications were recorded. Follow-up data, including postoperative course, clinical symptoms and duration of follow-up were documented. The five active bleedings discovered in procedures were managed in time, and the patients recovered without any new neurological symptoms compared with preoperation. However, of the two bleeding episodes that occurred after interventional procedures, one was detected half an hour later: the patient was remained comatose two months later after resection of right occipital hematoma; the other who encountered intraventricular and midbrain hemorrhage was treated conservatively and suffered Parinaud syndrome and hemianesthesia.

CONCLUSION

Periprocedural bleeding of AVMs embolization is considered a severe and devastating complication. The clinical course and prognosis of bleeding mostly depends on prompt detection and management. Interventional embolization is an effective method to manage bleeding during procedures, and the detection of risk factors and imaging signs of bleeding is extremely important.

Delayed thrombosis of the basilar artery after stenting for a basilar trunk dissection aneurysm. A case report and review of the literature

A 30-year-old man was referred in our department for treatment of a midbasilar trunk aneurysm. His presenting symptoms included headache and dizziness. A CT scan at another hospital showed no significant findings whereas a digital subtraction angiogram disclosed a dissecting aneurysm in the midbasilar trunk, and there was severe stenosis in the basilar artery. After discussion, we planned to use stent-assisted-coil embolization technique. During the procedure, a LEO stent (Balt, Montmorency, France) was implanted into the basilar artery across the aneurysm neck, but fearing acute basilar artery occlusion because of stent collapse or thrombus we did not fill coils into the aneurysm. After the procedure, the completion angiography demonstrated considerably decreased flow into the aneurysm, with stasis persisting into the venous phase of angiography. The patient awoke from general anaesthesia after the procedure and had no additional neurological symptoms, he was discharged three days later and used clopidogrel and aspirin for antiplatelet therapy. Six months later when he was admitted for a recheck, a DSA showed the basilar artery was occluded completely and the aneurysm had disappeared even though the patient remained neurologically normal.

The incidence of trigeminocardiac reflex in endovascular treatment of dural arteriovenous fistula with onyx

This paper reports the incidence of tri-geminocardiac reflex (TCR) in endovascular treatment of dural arteriovenous fistulas (DAVFs) with Onyx. The consecutive case histories of 45 patients with DAVFs, treated with Onyx transarterially and transvenously, from February 2005 to February 2008 at Beijing Tiantan Hospital, China, were retrospectively reviewed. The time period was limited as the anesthetic and intravascular procedure was performed under the same standardized anesthetic protocol and by the same team. The TCR rate was subsequently calculated. Of the 45 patients, five showed evidence of TCR during transarterial Onyx injection and transvenous DMSO injection. Their HR fell 50% during intravascular procedures compared with levels immediately before the stimulus. However, blood pressure values were stable in all cases. The TCR rate for all patients was 11.1% (95% CI, 4 to 24%), 7.7% (95% CI, 2 to 21%) in patients treated intraarterially and 33.3% (4 to 78%) in patients treated intravenously. Once HR has fallen, intravenous atropine is indicated to block the depressor response and prevention further TCR episodes. TCR may occur due to chemical stimulus of DMSO and Onyx cast formation under a standardized anesthetic protocol and should be blunted by atropine.

Subpopulations of stem-like cells in side population cells from the human bladder transitional cell cancer cell line T24

Cancer stem cells can be isolated from human tumours using specific cell surface markers. Bladder cancer cells, however, lack specific cell surface markers, making this approach impracticable. In this study an alternative method was used, involving isolation of side population cells to explore the stem cell characteristics of bladder cancer. Side population cells were isolated from the bladder transitional cell cancer cell line T24 and examined for potential stem cell characteristics related to proliferation, cell cycle distribution, self-renewal and differentiation. It was observed that T24 side population cells have stronger proliferative and colony formation abilities than non-side population cells. Side population cells were also more resistant to chemotherapy and radiotherapy, which may be due to expression of the ATP-binding cassette half-transporter, sub-family G, member 2 protein. Overall, the results suggest that side population cells from the human bladder transitional cell cancer cell line T24 harbour stem-like cells.

Intraarterial and intravenous treatment of transverse/sigmoid sinus dural arteriovenous fistulas

SUMMARY

Transverse/sigmoid sinus (TS) is the most common location for cerebral dural arteriovenous fistulas (DAVFs). Most of them are cured by venous embolization or a combination of arterial embolization and surgery/radiosurgery. Our goal was to reconsider the endovascular treatment strategy of TSDAVFs according to the new possibilities of arterial embolization using Onyx-18. Nineteen patients with TSDAVFs were included in a prospective study between 2004 and 2007. Three of them had type I, four had type IIa, six had type IIa+b, three had type III, and three had type IV fistulas. Three presented with subarachnoid hemorrhage. The approach routes, angiographic results, complications, and clinical outcome were assessed. The mean clinical follow-up period was 32.5 months. In one patient, the DAVF had been obliterated spontaneously at ten month follow-up. Complete angiographic cure was obtained in nine cases with one case of progressive thrombosis. Of these ten cures were achieved after a single procedure in seven out of ten patients who had not been embolized previously. Three patients were cured with sinus packing with prior arterial embolization. Among these 19 patients, 15 underwent follow-up angiography which confirmed the complete cure. Partial occlusion was obtained in nine patients, one was cured after additional surgery, and one underwent radiosurgery. Hallucination occurred in one completely cured patient on day one. Based on this experience, we believe that intraarterial Onyx may be the primary treatment of choice for patients with TSDAVFs. The applicability of this new embolic agent indicates the need for reconsideration of the treatment strategy for such fistulas.

Endovascular management for p2 aneurysms of the posterior cerebral artery. Experience on proximal occlusion of the p2 segmen

This study evaluated the outcomes of endovascular management for P2-segment aneurysms. From 2003 to 2008, 14 consecutive patients with P2 aneurysms were treated endovascularly by proximal P2 segment occlusion at our institution. The aneurysms included 12 P2a and two P2p aneurysms. Presenting symptoms were caused by subarachnoid hemorrhage (SAH) in six patients, stroke in five, and isolated headaches in three. Mean follow-up was 14 months. Twelve aneurysms were treated with proximal P2 segment occlusion without parent artery revascularization. Twelve aneurysms were at the P2a and two aneurysms at the P2p. Two patients developed hemianopsia after the procedure and one recovered completely within six months follow-up with one still persistent at 22-month follow-up. Proximal parent vessel occlusion was a relatively safe, effective treatment for P2 aneurysms that posed low risk for early or delayed ischemia or infarction.

Onyx migration in the endovascular management of intracranial dural arteriovenous fistulas

Onyx migration in the endovascular treatment of dural arteriovenous fistulas (dural AVFs) is uncommon. We describe five cases of Onyx migration to the heart and draining vein and its avoidance. Between February 2007 and August 2008, Onyx migration was encountered in five patients with dural AVFs treated endovascularly at our institute. Procedures performed under general anesthesia consisted of two arterial approaches and three venous approaches. Two patients with dural AVFs involving the transverse-sigmoid sinus were treated by transarterial embolization using Onyx-18 via the occipital artery and the posterior branch of the middle meningeal artery, respectively. A piece of Onyx was found in the right ventricle on post-embolization chest X-ray film in both patients, one developed tricuspid valve dysfunction requiring thoracic surgery and one was asymptomatic. The other three patients were treated with a combination of Onyx (34 or 18) and coils transvenously with venous Onyx migration leading to draining vein occlusion, one with dural AVF involving the tentorium died from venous rupture, two patients with bilateral dural AVFs of the cavernous sinus (one with deterioration of ocular symptoms and one without symptoms). Postoperative digital subtraction angiography confirmed the elimination of dural AVF in one patient, and residual fistulae in three patients. The follow-up study ranging from two to nine months (average, 4.5 months). Three patients recovered to their full activities, while one had visual disturbance. Although Onyx has been considered a controllable embolic agent, its migration to other locations causing clinical deterioration can occur. This problem should be noted and prevented.

Identification of tumor stem-like cells in a mouse myeloma cell line

We used colony formation assay in the soft agar media or the serum-free media, the methods of identifying BrdU-label-retaining cells and the SP cells as well as the tumorigenicity test in BALB/c mice, respectively, to analyze tumor stem like cells in the SP2/0 cell line. The results showed that a few SP2/0 cells were capable of forming colonies in the soft agar media, contained BrdU-label-immortal strand in the SP2/0 cell line. The SP2/0 cells in the serum-free media gained higher tumorigenicity in the BALB/c mice than the SP2/0 cells cultivated in the complete media did. Overall, only a few of the SP2/0 cells were found to possess the characteristics of tumor stem-like cells, such as high proliferative potency, more self-renewal and stronger tumorigenesis, or greater similarity to the tumor stem cells (TSCs) traits. The biology of tumor stem-like cells contributes to the identification of molecular targets important for future tumor therapy.

Rupture of Persistent Primitive Trigeminal Artery Aneurysm Associated with a Cavernous Sinus Fistula

We describe a patient with an aneurysm arising at a persistent primitive trigeminal artery ruptured to form a carotid-cavernous fistula. Coil occlusion of the carotid cavernous sinus fistula resulted in flow stasis of the persistent primitive trigeminal artery and resolution of symptoms. A ruptured aneurysm of the persistent primitive trigeminal artery can be associated with a carotid cavernous sinus fistula. Coil occlusion of the cavernous sinus and the PPTA is a safe and effective technique to treat this disease.

Treatment of giant intracranial aneurysms

We report on report the clinical outcome obtained in treatment of giant intracranial aneurysms (GAs). Between 2005 and 2007, 51 patients with 51 GAs presented at our hospital. Twentynine were treated with primary parent vessel occlusion without distal bypass and ten underwent treatment preserving the parent artery. Twelve patients could not be treated endovascularly. Selective embolization (including two remodeling techniques and two stent-coil mbolizations) resulted in only one cure. Two patients died as a result of subarachnoid hemorrhage periprocedurely. Twenty-nine patients treated primarily with parent vessel occlusion and three patients treated with covered stent were considered cured after their treatments. Only one patient treated with parent vessel occlusion experienced ischemia during follow-up, which resulted in a mild neurological deficit. Of the twelve patients who could not be treated endovascularly, one succumbed to surgery, four died while being treated conservatively, and three were lost to follow-up. Parent artery occlusion, covered stent and coil occlusion provide effective protection against bleeding. In treatment of paraclinoid GAs of the internal carotid rtery, the use of a stent, and stent-assisted coil embolization may be a pitfall.

A promising adjuvant to detachable coils for cavernous packing: onyx

Transvenous embolization of cavernous dural arteriovenous fistulae (CDAVFs) with Onyx has recently been reported. This study was undertaken to assess the value of Onyx in transvenous treatment of CDAVFs. We retrospectively reviewed 18 patients who underwent transvenous embolization for CDAVFs of Barrow Type D with detachable coils and Onyx at our institution over five years. Patients were divided into two groups: group A, patients who had been treated with detachable coils; group B, patients who had been treated with a combination of detachable coils and Onyx. The approach routes, angiographic results, complications and clinical outcome were assessed for both groups. Eighteen patients with CDAVFs of Barrow Type D were treated: nine women and nine men; mean age was 41.9 years. Eleven patients treated by 19 procedures of transvenous coiling belonged to group A. Seven patients treated by eight procedures of transvenous Onyx injection belonged to group B. The periprocedural complication rate associated with coiling for both groups was 18.2% vs 16.7% with Onyx. The duration of the procedure in both groups was 6.77-/+2.49 hours vs 3.75-/+1.63 hours with coiling vs Onyx, and the cost of Onyx was cheaper than coils. An excellent outcome was achieved in both groups: 90.9% vs 100% (group A vs group B). Our results associated with both modalities of CDAVFs treatment with clinical outcome show that transvenous embolization with Onyx is a safe alternative to detachable coils in the treatment of CDAVFs. However, more cases need to be evaluated.

SARS-coronavirus modulation of myocardial ACE2 expression and inflammation in patients with SARS

BACKGROUND

Angiotensin converting enzyme 2 (ACE2), a monocarboxylase that degrades angiotensin II to angiotensin 1-7, is also the functional receptor for severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) and is highly expressed in the lungs and heart. Patients with SARS also suffered from cardiac disease including arrhythmias, sudden cardiac death, and systolic and diastolic dysfunction.

MATERIALS AND METHODS

We studied mice infected with the human strain of the SARS-CoV and encephalomyocarditis virus and examined ACE2 mRNA and protein expression. Autopsy heart samples from patients who succumbed to the SARS crisis in Toronto (Canada) were used to investigate the impact of SARS on myocardial structure, inflammation and ACE2 protein expression.

RESULTS

Pulmonary infection with the human SARS-CoV in mice led to an ACE2-dependent myocardial infection with a marked decrease in ACE2 expression confirming a critical role of ACE2 in mediating SARS-CoV infection in the heart. The SARS-CoV viral RNA was detected in 35% (7/20) of autopsied human heart samples obtained from patients who succumbed to the SARS crisis during the Toronto SARS outbreak. Macrophage-specific staining showed a marked increase in macrophage infiltration with evidence of myocardial damage in patients who had SARS-CoV in their hearts. The presence of SARS-CoV in the heart was also associated with marked reductions in ACE2 protein expression.

CONCLUSIONS

Our data show that SARS-CoV can mediate myocardial inflammation and damage associated with down-regulation of myocardial ACE2 system, which may be responsible for the myocardial dysfunction and adverse cardiac outcomes in patients with SARS.