A Special Clinical Scenario for Transcatheter Aortic Valve Replacement: "Iatrogenic Double-Outlet" Left Ventricle.

A 67-year-old man with a history of chest radiotherapy and severe aortic valve stenosis with calcification of the ascending aortic wall underwent implantation of an apicoaortic conduit from the left ventricular apex to the descending aorta. Eight years later, he presented with progressive exertional dyspnea. Imaging revealed severe native aortic valve insufficiency and calcification, with worsening left ventricular function. We decided to leave the apicoaortic conduit intact and perform transcatheter aortic valve replacement with a balloon-expandable prosthesis. Despite concerns that eliminating the obstruction across the native left ventricular outflow tract might decrease conduit flow and eventually cause graft thrombosis and peripheral embolization, we elected to move forward after a multidisciplinary discussion. The procedure resulted in angiographically and qualitatively similar forward flow across the newly implanted prosthesis and the existing apicoaortic conduit, with no hemodynamic or electrical dysfunction. The patient was discharged from the hospital the next day. At the 1-month follow-up visit, the patient felt well and reported marked functional improvement, with minimal symptoms during moderate to heavy exertion. The stroke volume index across the new bioprosthetic valve was low (13 mL/m2 at 1 mo and 18 mL/m2 at 1 y), suggesting that a substantial amount of blood was still exiting the ventricle through the left ventricle-to-aorta conduit. This report offers some guidance for treating patients with existing apicoaortic conduits and suggests that transcatheter aortic valve replacement is safe and effective if native aortic valve insufficiency develops.

Hemodynamic outcomes after valve-in-valve transcatheter aortic valve replacement: a single-center experience.

BACKGROUND: Valve-in-valve transcatheter aortic valve replacement (ViV-TAVR) has emerged as a safe, effective alternative to redo aortic valve surgery in high-risk patients with degenerated surgical bioprosthetic valves. However, ViV-TAVR has been associated high postprocedural valvular gradients, compared with TAVR for native-valve aortic stenosis. METHODS: We performed a retrospective study of all patients who underwent ViV-TAVR for a degenerated aortic valve bioprosthesis between January 1, 2013 and March 31, 2019 at our center. The primary outcome was postprocedural mean aortic valve gradient. Outcomes were compared across surgical valve type (stented versus stentless), surgical valve internal diameter (≤19 versus >19 mm), and transcatheter aortic valve type (self-expanding vs. balloon-expandable). RESULTS: Overall, 89 patients underwent ViV-TAVR. Mean age was 69.0±12.6 years, 61% were male, and median Society of Thoracic Surgeons Predicted Risk of Mortality score was 5.4 [interquartile range, 3.2-8.5]. Bioprosthesis mode of failure was stenotic (58% of patients), regurgitant (24%), or mixed (18%). The surgical valve was stented in 75% of patients and stentless in 25%. The surgical valve's internal diameter was ≤19 mm in 45% of cases. A balloon-expandable transcatheter valve was used in 53% of procedures. Baseline aortic valve area and mean gradients were 0.87±0.31 cm2 and 36±18 mmHg, respectively. These improved after ViV-TAVR to 1.38±0.55 cm2 and 18±11 mmHg at a median outpatient follow-up of 331 [67-394] days. Higher postprocedural mean gradients were associated with surgical valves having an internal diameter ≤19 mm (24±13 versus 16±8, P=0.002) and with stented surgical valves (22±11 versus 12±6, P<0.001). CONCLUSIONS: ViV-TAVR is an effective option for treating degenerated surgical aortic bioprostheses, with acceptable hemodynamic outcomes. Small surgical valves and stented surgical valves are associated with higher postprocedural gradients.

Transcatheter aortic valve replacement after chest radiation: A propensity-matched analysis.

BACKGROUND: Chest radiation therapy (CRT) for malignant thoracic neoplasms is associated with development of valvular heart disease years later. As previous radiation exposure can complicate surgical treatment, transcatheter aortic valve replacement (TAVR) has emerged as an alternative. However, outcomes data are lacking for TAVR patients with a history of CRT. METHODS: We conducted a retrospective study of all patients who underwent a TAVR procedure at a single institution between September 2012 and November 2018. Among 1341 total patients, 50 had previous CRT. These were propensity-matched in a 1:2 ratio to 100 patients without history of CRT. Thirty-day adverse events were analyzed with generalized estimating equation models. Overall mortality was analyzed with stratified Cox regression modelling. RESULTS: Median clinical follow-up was 24 months (interquartile range [IQR], 12-44 months). There was no difference between CRT and non-CRT patients in overall mortality (hazard ratio [HR] 0.84 [0.37-1.90], P = 0.67), 30-day mortality (HR 3.1 [0.49-20.03], P = 0.23), or 30-day readmission rate (HR 1.0 [0.43-2.31], P = 1). There were no differences in the rates of most adverse events, but patients with CRT history had higher rates of postprocedural respiratory failure (HR 3.63 [1.32-10.02], P = 0.01) and permanent pacemaker implantation (HR 2.84 [1.15-7.01], P = 0.02). CONCLUSIONS: For patients with aortic valve stenosis and previous CRT, TAVR is safe and effective, with outcomes similar to those in the general aortic stenosis population. Patients with history of CRT are more likely to have postprocedural respiratory failure and to require permanent pacemaker implantation.

Risk stratification with exercise N(13)-ammonia PET in adults with anomalous right coronary arteries.

OBJECTIVE: In adults with an interarterial and intramural course of an anomalous right coronary artery from the left sinus (AAORCA), surgical unroofing is recommended in the setting of myocardial ischaemia. However, data regarding functional testing are limited, and the management of adults without ischaemia is unclear. To evaluate these patients, we employed an exercise N(13)-ammonia positron emission tomography (PET) protocol. We hypothesised that patients with typical angina and exertional dyspnoea would be more likely to have ischaemia and that patients without ischaemia could be managed conservatively. METHODS: Between July 2008 and December 2014, we retrospectively identified 27 consecutive patients >18 years old with an interarterial and intramural course of an AAORCA who had exercise N(13)-ammonia PET. RESULTS: The majority of patients had anatomic delineation with cardiac CT (25, 93%), and most patients had chest pain (24, 89%). Myocardial ischaemia with PET was common (13, 48%), and ischaemia was more likely in patients with typical angina and exertional dyspnoea (p<0.05). Surgery was performed in 12 patients including 11 patients with ischaemia. At a median follow-up of 245 days, there were no deaths in patients with surgery or in patients managed conservatively. CONCLUSIONS: In patients with an interarterial and intramural course of an AAORCA, typical angina and exertional dyspnoea are associated with ischaemia on exercise N(13)-ammonia PET. Referral for surgical unroofing in symptomatic patients with ischaemia on exercise N(13)-ammonia PET and initial conservative management in patients without ischaemia seems appropriate, though larger studies with long-term follow-up are needed.

Temporal Variability of Global Longitudinal Strain in Stable Patients Undergoing Chemotherapy With Trastuzumab.

Global longitudinal strain (GLS) is used to evaluate left ventricular (LV) performance after chemotherapy. Differentiating between reduction in GLS due to clinical change and normal temporal variability in measurement remains a challenge. We quantified interobserver, test-retest variability of GLS by expert observers in relation to variability of GLS quantified for clinical assessment by sonographers in our laboratory. We examined the temporal variability of GLS in 30 patients with normal LV ejection fraction (LVEF >53%) undergoing chemotherapy in the absence of change in medications and clinical symptoms in up to 5 sequential echocardiograms. GLS was quantified using EchoPAC (GE Healthcare, Milwaukee, Wisconsin) and 2-dimensional biplane LVEF was measured from 4- and 2- chamber views. Interobserver test-retest variability of GLS measured in 10 random patients by 2 expert readers was calculated using a one-way analysis of variance. Square root of mean squared error provided the SEM for temporal variability. Baseline LVEF was 59.3 ± 5.1% and remained relatively unchanged over 12 months, p = 0.87. Temporal variability of GLS measured by sonographers was 1.28% and similar to interobserver test-retest variability of GLS measured by expert observers, 1.12% (p = 0.17). Maximum detectable difference in GLS measured by expert observers was similar to that derived from sequential measurements of GLS (3.2% vs 3.6%, respectively). Temporal variability of GLS among clinically stable patients is 1.28% and similar to interobserver test-retest variability of 1.12% measured by expert observers. In conclusion, a reduction in strain >3.2% during sequential echocardiograms under these conditions may be significant.

Hypereosinophilic syndrome associated with ulcerative colitis presenting with recurrent Loeffler's endocarditis and left ventricular thrombus treated successfully with immune suppressive therapy and anticoagulation.

We reported a case of a 28-year-old Caucasian woman with hypereosinophilic syndrome (HES) associated with ulcerative colitis who presented on separate occasions with Loeffler's endocarditis. She was admitted in 2008 with fever, headache, confusion and visual loss. Diagnostic workup uncovered an eosinophilia of 3.1×109/L and major ECG abnormalities. Subsequent echocardiography revealed left ventricular wall motion abnormalities with mural thrombus. MRI brain scan showed multiple white matter lesions consistent with acute infarcts. She recovered rapidly with corticosteroids and anticoagulation. Four years later she re-presented with headache, fatigue and an eosinophilia of 13.4×109/L. This occurred 3 months after cessation of immunosuppression and within 12 months of total colectomy for fulminant ulcerative colitis. Echocardiography was suggestive of hypereosinophilic endomyocardial fibrosis with left ventricular thrombus. Anticoagulation and corticosteroids were resumed with good effect. This report highlights the findings, treatment and outcome of ulcerative colitis-associated HES manifesting as recurrent Loeffler's endocarditis.

Thioredoxin-1 gene therapy enhances angiogenic signaling and reduces ventricular remodeling in infarcted myocardium of diabetic rats.

BACKGROUND: The present study evaluated the reversal of diabetes-mediated impairment of angiogenesis in a myocardial infarction model of type 1 diabetic rats by intramyocardial administration of an adenoviral vector encoding thioredoxin-1 (Ad.Trx1). Various studies have linked diabetes-mediated impairment of angiogenesis to dysfunctional antioxidant systems in which thioredoxin-1 plays a central role. METHODS AND RESULTS: Ad.Trx1 was administered intramyocardially in nondiabetic and diabetic rats immediately after myocardial infarction. Ad.LacZ was similarly administered to the respective control groups. The hearts were excised for molecular and immunohistochemical analysis at predetermined time points. Myocardial function was measured by echocardiography 30 days after the intervention. The Ad.Trx1-administered group exhibited reduced fibrosis, oxidative stress, and cardiomyocyte and endothelial cell apoptosis compared with the diabetic myocardial infarction group, along with increased capillary and arteriolar density. Western blot and immunohistochemical analysis demonstrated myocardial overexpression of thioredoxin-1, heme oxygenase-1, vascular endothelial growth factor, and p38 mitogen-activated protein kinase-beta, as well as decreased phosphorylated JNK and p38 mitogen-activated protein kinase-alpha, in the Ad.Trx1-treated diabetic group. Conversely, we observed a significant reduction in the expression of vascular endothelial growth factor in nondiabetic and diabetic animals treated with tin protoporphyrin (SnPP, a heme oxygenase-1 enzyme inhibitor), even after Ad.Trx1 therapy. Echocardiographic analysis after 4 weeks of myocardial infarction revealed significant improvement in myocardial functional parameters such as ejection fraction, fractional shortening, and E/A ratio in the Ad.Trx1-administered group compared with the diabetic myocardial infarction group. CONCLUSIONS: This study demonstrates for the first time that impairment of angiogenesis and myocardial dysfunction can be regulated by Ad.Trx1 gene therapy in streptozotocin-induced diabetic rats subjected to infarction.

Thioredoxin-1 gene delivery induces heme oxygenase-1 mediated myocardial preservation after chronic infarction in hypertensive rats.

BACKGROUND: Hypertension, the major risk factor for many cardiovascular diseases, is a result of multiple causes along with excessive generation of reactive oxygen species (ROS) resulting in imbalance of redox status. METHODS: In this study, we investigated the therapeutic potential of Adenoviral-Thioredoxin-1 (Adeno-Trx-1) in spontaneous hypertensive rats (SHRs) at a dosage of 1 x 10(9) pfu. The rats were assigned as normotensive Wistar-Kyoto (WKY), SHR, SHR + Adeno-Lac-Z (SHRLac-Z), and SHR + Adeno-Trx-1 (SHRTrx-1). Echo-guided injection of adeno virus was done 48 h before permanent myocardial infarction (MI) by left anterior descending coronary artery (LAD) occlusion. RESULTS: Decreased infarct size (52 +/- 4.1% vs. 67 +/- 6.1%), number of apoptotic cardiomyocytes (161 +/- 14.8 vs. 240 +/- 22.2), left ventricular inner diameter (7 +/- 0.33 vs. 9 +/- 0.46 mm), increased ejection fraction (52 +/- 6.3 vs. 42 +/- 3.3%), and fractional shortening (28 +/- 1.8 vs. 22 +/- 2.04 %) was observed in the SHRTrx-1 compared to SHR. Western Blot and immunohistochemical analysis demonstrated increased expression of Trx-1, HO-1, and Bcl-2 in the SHRTrx-1 compared to SHR. In addition, increased HO-1 activity was also observed in SHRTrx-1 as compared to SHR and SHRLac-Z groups. CONCLUSION: Our study demonstrates that the cardioprotective effect of Adeno-Trx-1 gene therapy in SHR is Trx-1/HO-1/Bcl-2 mediated and may represent future target to develop therapy against hypertension associated cardiac failure.

Strategic targets to induce neovascularization by resveratrol in hypercholesterolemic rat myocardium: role of caveolin-1, endothelial nitric oxide synthase, hemeoxygenase-1, and vascular endothelial growth factor.

Endothelial dysfunction and impaired angiogenesis constitute a hallmark of hypercholesterolemia. This study was designed to examine the effects of resveratrol, an antioxidant with lipid-lowering properties similar to those of statins, on neovascularization along with caveolar interaction with proangiogenic molecules in hypercholesterolemic rats. Animals were divided into: rats maintained on a normal diet (control group); rats maintained on a 5% high-cholesterol diet for 8 weeks (HC group); and rats maintained on a 5% high-cholesterol diet for 8 weeks and administered resveratrol (20 mg/kg) orally for 2 weeks (HCR group). Myocardial infarction was induced by ligating the left anterior descending artery. Herein we examined a novel method for stimulating myocardial angiogenesis by pharmacological preconditioning with resveratrol at both the capillary and arteriolar levels and the potential role of hemeoxygenase-1, endothelial nitric oxide synthase and caveolin-1 in mediating such a response. We also investigated the functional relevance of such treatment by assessing whether the induced neovascularization can help preserve left ventricle-contractile functional reserve in the setting of a chronic hypercholesterolemic condition. Four weeks after sham surgery and left anterior descending artery occlusion, rats underwent echocardiographic evaluation, which revealed improvement in ejection fraction and fractional shortening in the HCR group compared with the HC group. Left ventricular tissue sections displayed increased capillary and arteriolar density in the HCR group compared with the HC group. Western blot analysis revealed downregulation of vascular endothelial growth factor and hemeoxygenase-1 and increased association of caveolin-1 eNOS in the HC group, decreasing the availability of eNOS to the system; which was reversed with resveratrol treatment in the HCR group. This study was further validated in cardiac-specific hemeoxygenase-1-overexpressed mice assuming molecular cross-talk between the targets. Hence, our data identified potential regulators that primarily attenuate endothelial dysfunction by resveratrol therapy in hypercholesterolemic myocardium.

Sildenafil-mediated neovascularization and protection against myocardial ischaemia reperfusion injury in rats: role of VEGF/angiopoietin-1.

Sildenafil citrate (SC), a drug for erectile dysfunction, is now emerging as a cardiopulmonary drug. Our study aimed to determine a novel role of sildenafil on cardioprotection through stimulating angiogenesis during ischaemia (I) reperfusion (R) at both capillary and arteriolar levels and to examine the role of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) in this mechanistic effect. Rats were divided into: control sham (CS), sildenafil sham (SS), control+IR (CIR) and sildenafil+IR (SIR). Rats were given 0.7 mg/kg, (i.v) of SC or saline 30 min. before occlusion of left anterior descending artery followed by reperfusion (R). Sildenafil treatment increased capillary and arteriolar density followed by increased blood flow (2-fold) compared to control. Treatment with sildenafil demonstrated increased VEGF and Ang-1 mRNA after early reperfusion. PCR data were validated by Western blot analysis. Significant reduction in infarct size, cardiomyocyte and endothelial apoptosis were observed in SC-treated rats. Increased phosphorylation of Akt, eNOS and expression of anti-apoptotic protein Bcl-2, and thioredoxin, hemeoxygenase-1 were observed in SC-treated rats. Echocardiography demonstrated increased fractional shortening and ejection fraction following 45 days of reperfusion in the treatment group. Stress testing with dobutamine infusion and echocardiogram revealed increased contractile reserve in the treatment group. Our study demonstrated for the first time a strong additional therapeutic potential of sildenafil by up-regulating VEGF and Ang-1 system, probably by stimulating a cascade of events leading to neovascularization and conferring myocardial protection in in vivo I/R rat model.

Upregulation of myocardial 11S-activated proteasome in experimental hyperglycemia.

This study examined the hypothesis that the ubiquitin proteasome system (UPS) degrades proteins damaged by exposure to hyperglycemia. Experimental hyperglycemia was induced in male rats by treatment with streptozotocin. After 30 days, echocardiography confirmed the presence of cardiomyopathy as ejection fraction, fractional shortening, and diastolic function (E/A ratio) were decreased, and chamber diameter was increased in hyperglycemic animals. Proteasome non-ATP-dependent chymotryptic activity was increased over 2-fold in hyperglycemic hearts, but the ATP-dependent activity was decreased and levels of ubiquitinated proteins were increased. Protein levels of the PA28alpha of the 11S-activator ring were increased by 128% and the PA28beta subunit increased by 58% in the hyperglycemic hearts. The alpha3 subunit of the 20S-proteasome was increased by 82% while the catalytic beta5 subunit was increased by 68% in hyperglycemic hearts. Protein oxidation as indicated by protein carbonyls was significantly higher in hyperglycemic hearts. These studies support the conclusion that the UPS becomes dysfunctional during long term hyperglycemia. However, 11S-activated proteasome was increased suggesting a response to oxidative protein damage and a potential role for this form of the proteasome in a cardiac pathophysiology.

Secoisolariciresinol diglucoside induces neovascularization-mediated cardioprotection against ischemia-reperfusion injury in hypercholesterolemic myocardium.

Hypercholesterolemia (HC) induced endothelial cell dysfunction and decreased endothelial nitric oxide formation results in impaired angiogenesis and subsequent cardiovascular disorders. Therapeutic angiogenesis is known to be a novel strategy for treatment of patients with ischemic heart disease. We have shown that secoisolariciresinol diglucoside (SDG) is angiogenic as well as cardioprotective against myocardial ischemia. In the present study, we examined the efficacy of SDG in a hypercholesterolemic myocardial infarction (MI) model. The rats were maintained on a normal and high cholesterol diet (2%) for 8 weeks followed by oral administration of SDG (20 mg/kg) for 2 weeks. The rats were divided into four groups (n=24 in each): Control (C); SDG control (SDG); HC; and HC+SDG (HSDG). Isolated hearts subjected to 30 min of global ischemia followed by 120 min of reperfusion were used to measure the cardiac functions, infarct size and to examine the protein expression profile. After treatment, MI was induced by ligating the left anterior descending artery. Echocardiographic parameters were examined 30 days after MI. Significant reduction in total cholesterol, LDL-cholesterol, triglycerides and an increase in HDL-cholesterol levels were observed in HSDG as compared to the HC. Decreased infarct size was observed in the HSDG group (43%) compared to the HC (54%). Increased phosphorylation of endothelial nitric oxide synthase (p-eNOS) (3.1-fold), vascular endothelial growth factor (1.9-fold) and heme oxygenase-1 (2.3-fold) was observed in the HSDG group as compared to the HC group. Significant improvement in left ventricular functions was also observed in the HSDG group as evidenced by increased ejection fraction (55% vs. 45%), fractional shortening (28% vs. 22%) and decreased left ventricular inner diameter in systole (8 vs. 6 mm) in HSDG compared to HC. Moreover, MI model has shown increased capillary density (2531 vs. 1901) and arteriolar density (2.6 vs. 1.8) in SDG-treated rats as compared to the HC. The increased capillary and arteriolar density along with increased left ventricular functions on SDG treatment might be due to increased HO-1, VEGF and p-eNOS expression. In conclusion, our study demonstrates for the first time that SDG treatment reduces ventricular remodeling by neovascularization of the infarcted HC myocardium.

Resveratrol alleviates cardiac dysfunction in streptozotocin-induced diabetes: Role of nitric oxide, thioredoxin, and heme oxygenase.

Excessive oxidative stress has been implicated in the pathology and complications of diabetes, which leads to myocardial ischemia reperfusion injury. The present study was designed to examine whether resveratrol (trans-3,5,4'-trihydroxystilbene), a polyphenolic compound present in red wine has a direct cardioprotective effect on diabetic myocardium. Resveratrol (2.5 mg/kg body wt/day) and L-NAME (25 mg/kg body wt/day) were administered orally for 15 days to streptozotocin (65 mg/kg)-induced diabetic rats. Sprague Dawley rats were divided into 5 groups: (i) control, (ii) diabetic, (iii) diabetic+resveratrol, (iv) diabetic+resveratrol+L-NAME (nitric oxide synthase inhibitor), and (v) diabetic+L-NAME. In our present study resveratrol demonstrated significant reduction in glucose level in diabetic rats. After the treatment, the hearts were excised and subjected to 30 min of global ischemia followed by 2 h of reperfusion. Resveratrol-treated diabetic rats demonstrated significant reduction in glucose levels as compared to the nontreated diabetic animals, and improved left ventricular function throughout reperfusion compared to the diabetic or L-NAME-treated animals (dp/dt(max) 1457+/-51 vs 999+/-44 mm Hg/s at 120 min reperfusion). Cardioprotection from ischemic injury in resveratrol-treated diabetic rats showed decreased infarct size (42% vs 51%) and cardiomyocyte apoptosis (35% vs 40%) as compared with diabetic animals. Resveratrol produced significant induction of p-AKT, p-eNOS, Trx-1, HO-1, and VEGF in addition to increased activation of MnSOD activity in diabetic animals compared to nondiabetic animals. However treatment with L-NAME in resveratrol-treated and nontreated diabetic animals demonstrated significant downregulation of the above-noted protein expression profile and MnSOD activity. In the present study we found that the mechanism(s) responsible for the cardioprotective effect of resveratrol in the diabetic myocardium include upregulation of Trx-1, NO/HO-1, and VEGF in addition to increased MnSOD activity and reduced blood glucose level. Thus this study shows a novel mechanism of pharmacological preconditioning with resveratrol in the diabetic myocardium.

Redox regulation of ischemic preconditioning is mediated by the differential activation of caveolins and their association with eNOS and GLUT-4.

Reactive oxygen species (ROS) generated during ischemia-reperfusion (I/R) enhance myocardial injury, but brief periods of myocardial ischemia followed by reperfusion [ischemic preconditioning (IP)] induce cardioprotection. Ischemia is reported to stimulate glucose uptake through the translocation of GLUT-4 from the intracellular vesicles to the sarcolemma. In the present study we demonstrated involvement of ROS in IP-mediated GLUT-4 translocation along with increased expression of caveolin (Cav)-3, phospho (p)-endothelial nitric oxide synthase (eNOS), p-Akt, and decreased expression of Cav-1. The rats were divided into the following groups: 1) control sham, 2) N-acetyl-L-cysteine (NAC, free radical scavenger) sham (NS), 3) I/R, 4) IP + I/R (IP), and 5) NAC + IP (IPN). IP was performed by four cycles of 4 min of ischemia and 4 min of reperfusion followed by 30 min of ischemia and 3, 24, 48 h of reperfusion, depending on the protocol. Increased mRNA expression of GLUT-4 and Cav-3 was observed after 3 h of reperfusion in the IP group compared with other groups. IP increased expression of GLUT-4, Cav-3, and p-AKT and p-eNOS compared with I/R. Coimmunoprecipitation demonstrated decreased association of Cav-1/eNOS in the IP group compared with the I/R group. Significant GLUT-4 and Cav-3 association was also observed in the IP group. This association was disrupted when NAC was used in conjunction with IP. It clearly documents a significant role of ROS signaling in Akt/eNOS/Cav-3-mediated GLUT-4 translocation and association in IP myocardium. In conclusion, we demonstrated a novel redox mechanism in IP-induced eNOS and GLUT-4 translocation and the role of caveolar paradox in making the heart euglycemic during the process of ischemia, leading to myocardial protection in a clinically relevant rat ischemic model.

Statin and resveratrol in combination induces cardioprotection against myocardial infarction in hypercholesterolemic rat.

Hypercholesterolemia (HC) is a common health problem that significantly increases risk of cardiovascular disease. Both statin (S) and resveratrol (R) demonstrated cardioprotection through nitric oxide-dependent mechanism. Therefore, the present study was undertaken to determine whether combination therapy with statin and resveratrol is more cardioprotective than individual treatment groups in ischemic rat heart model. The rats were fed with 2% high cholesterol diet and after 8 weeks of high cholesterol diet the animals were treated with statin (1 mg/kg bw/day) and resveratrol (20 mg/kg bw/day) for 2 weeks. The rats were assigned to: (1) Control (C), (2) HC, (3) HCR, (4) HCS and (5) HCRS. The hearts, subjected to 30-min global ischemia followed by 120-min reperfusion were used as experimental model. The left ventricular functional recovery (+dp/dt(max)) was found to be significantly better in the HCRS (1926+/-43), HCR (1556+/-65) and HCS (1635+/-40) compared to HC group (1127+/-16). The infarct sizes in the HCRS, HCS and HCR groups were 37+/-3.6, 43+/-3.3 and 44+/-4.2 respectively compared to 53+/-4.6 in HC. The lipid level was found to be decreased in all the treatment groups when compared to HC more significantly in HCS and HCRS groups when compared to HCR. Increased phosphorylation of Akt and eNOS was also observed in all the treatment groups resulting in decreased extent of cardiomyocyte apoptosis but the extent of reduction in apoptosis was more significant in HCRS group compared to all other groups. In vivo rat myocardial infarction (MI) model subjected to 1 week of permanent left descending coronary artery (LAD) occlusion documented increased capillary density in HCR and HCRS treated group when compared to HCS treatment group. We also documented increased beta-catenin translocation and increased VEGF mRNA expression in all treatment groups. Thus, we conclude that the acute as well as chronic protection afforded by combination treatment with statin and resveratrol may be due to pro-angiogenic, anti-hyperlipidemic and anti-apoptotic effects and long-term effects may be caused by increased neo-vascularization of the MI zone leading to less ventricular remodeling.