Fatal myocardial rupture after acute myocardial infarction complicated by heart failure, left ventricular dysfunction, or both: the VALsartan In Acute myocardial iNfarcTion Trial (VALIANT).

BACKGROUND: Myocardial rupture is a relatively rare and usually fatal complication of myocardial infarction (MI). Early recognition of patients at greatest risk of myocardial rupture provides an opportunity for early intervention. METHODS: VALIANT was a double-blind, randomized, controlled trial comparing valsartan, captopril, and their combination in high-risk patients post-MI. Myocardial rupture was identified by autopsy (available in 138/589 patients dying within 30 days of index MI), echocardiography, direct surgical visualization, or presence of hemopericardium. An independent clinical end points committee reviewed medical records for all deaths or suspected nonfatal cardiovascular events. RESULTS: Rupture was identified in 45 (0.31%) patients enrolled in VALIANT, occurring 9.8 +/- 6.0 days after the qualifying MI. Rupture accounted for 7.6% (45/589) of all deaths occurring in the first 30 days of follow-up and 24% (33/138) of deaths in which autopsies were obtained. Compared with survivors, rupture was associated with increased age, hypertension, increased Killip class, lower estimated glomerular filtration rate, and Q wave MI, and inversely related to beta-blocker and diuretic use. Compared with patients who died of other causes within 30 days, patients with myocardial rupture were more likely to have had an inferior MI, Q wave MI, or hypertension; to have used oral anticoagulants; or to have received thrombolytic therapy. CONCLUSIONS: Although rare, myocardial rupture accounted for nearly one fourth of all deaths within the first 30 days after high-risk MI, suggesting an estimated incidence of approximately 1% within the first 30 days. A number of clinical characteristics may identify post-MI patients at higher risk of myocardial rupture.

Long-term vasodilator therapy in patients with severe aortic regurgitation.

BACKGROUND: Vasodilator therapy can reduce the left ventricular volume and mass and improve left ventricular performance in patients with aortic regurgitation. Accordingly, it has been suggested that such therapy may reduce or delay the need for aortic-valve replacement. METHODS: We randomly assigned 95 patients with asymptomatic severe aortic regurgitation and normal left ventricular function to receive open-label nifedipine (20 mg every 12 hours), open-label enalapril (20 mg per day), or no treatment (control group) to identify the possible beneficial effects of vasodilator therapy on left ventricular function and the need for aortic-valve replacement. RESULTS: After a mean of seven years of follow-up, the rate of aortic-valve replacement was similar among the groups: 39 percent in the control group, 50 percent in the enalapril group, and 41 percent in the nifedipine group (P=0.62). In addition, there were no significant differences among the groups in aortic regurgitant volume, left ventricular size, left ventricular mass, mean wall stress, or ejection fraction. One year after valve replacement, the left ventricular end-diastolic diameter and end-systolic diameter had decreased to a similar degree among the patients who underwent surgery in each of the three groups, and all the patients had a normal ejection fraction. CONCLUSIONS: Long-term vasodilator therapy with nifedipine or enalapril did not reduce or delay the need for aortic-valve replacement in patients with asymptomatic severe aortic regurgitation and normal left ventricular systolic function. Furthermore, such therapy did not reduce the aortic regurgitant volume, decrease the size of the left ventricle, or improve left ventricular function.

Cardiologists' awareness and perceptions of guidelines for chronic heart failure. The ADDress your Heart survey.

BACKGROUND: Several surveys show that patients with chronic heart failure (CHF) are sub-optimally managed and treatment guidelines are not implemented in clinical practice. AIMS: To investigate awareness and perceptions of the 2005 European Society of Cardiology (ESC) guidelines for CHF. METHODS: 467 cardiologists from seven European countries completed an on-line interview using a validated, semi-structured questionnaire including questions about awareness and relevance of CHF guidelines. To assess agreement with ESC guidelines, three fictitious patient cases were presented and respondents' management choices compared with those of an expert panel based on the guidelines. RESULTS: Awareness of CHF guidelines was high, with 98% aware of any guideline and 65% aware of ESC guidelines. ESC guidelines were considered relevant (51%) or very relevant (38%) for guiding treatment decisions. Up to 92% of respondents perceived that they adhered to the ESC guidelines. For the patient cases,

Low-pressure cardiac tamponade: clinical and hemodynamic profile.

BACKGROUND: Low-pressure cardiac tamponade is a form of cardiac tamponade in which a comparatively low pericardial pressure results in cardiac compression because of low filling pressure. This syndrome is poorly characterized because only isolated cases have been reported. We conducted a study of its clinical and hemodynamic profiles. METHODS AND RESULTS: From 1986 through 2004, we evaluated all patients at our institution with combined pericardiocentesis and cardiac catheterization. We identified those patients who fulfilled catheterization-based criteria of low-pressure cardiac tamponade and compared their clinical and catheterization data with those of patients with classic tamponade. A total of 1429 patients with pericarditis were evaluated, 279 of whom underwent combined pericardiocentesis and catheterization. Criteria of low-pressure cardiac tamponade were met in 29, whereas 114 had criteria of classic cardiac tamponade. Patients with low-pressure tamponade less frequently had clinical signs of tamponade, but the rate of constitutional symptoms, use of diuretics, and echocardiographic findings of tamponade were similar in both groups. Patients with low-pressure tamponade showed a significant increase in cardiac output after pericardiocentesis, but they usually had less severe cardiac tamponade compared with patients with classic tamponade. Prognosis was related mainly to the underlying disease. CONCLUSIONS: Low-pressure cardiac tamponade was identified in 20% of patients with catheterization-based criteria of tamponade. Clinical recognition may be difficult because of the absence of typical physical findings of tamponade in most patients. Although some patients are critically ill, most show a stable clinical condition. However, these patients obtain a clear benefit from pericardiocentesis.

Effusive-constrictive pericarditis.

BACKGROUND: Effusive-constrictive pericarditis is an uncommon pericardial syndrome characterized by concomitant tamponade, caused by tense pericardial effusion, and constriction, caused by the visceral pericardium. We conducted a prospective study of its clinical evolution and management. METHODS: From 1986 through 2001, all patients with effusive-constrictive pericarditis were prospectively evaluated. Combined pericardiocentesis and cardiac catheterization were performed in all patients, and pericardiectomy was performed in those with persistent constriction. Follow-up ranged from 1 month to 15 years (median, 7 years). RESULTS: A total of 1184 patients with pericarditis were evaluated, 218 of whom had tamponade. Of these 218, 190 underwent combined pericardiocentesis and catheterization. Fifteen of these patients had effusive-constrictive pericarditis and were included in the study. All patients presented with clinical tamponade; however, concomitant constriction was recognized in only seven patients. At catheterization, all patients had elevated intrapericardial pressure (median, 12 mm Hg; interquartile range, 7 to 18) and elevated right atrial and end-diastolic right and left ventricular pressures. After pericardiocentesis, the intrapericardial pressure decreased (median value, -5 mm Hg; interquartile range, -5 to 0), whereas right atrial and end-diastolic right and left ventricular pressures, although slightly reduced, remained elevated, with a dip-plateau morphology. The causes were diverse, and death was mainly related to the underlying disease. Pericardiectomy was required in seven patients, all of whom had involvement of the visceral pericardium. Three patients had spontaneous resolution. CONCLUSIONS: Effusive-constrictive pericarditis is an uncommon pericardial syndrome that may be missed in some patients who present with tamponade. Although evolution to persistent constriction is frequent, idiopathic cases may resolve spontaneously. In our opinion, extensive epicardiectomy is the procedure of choice in patients requiring surgery.

Body mass index, prognosis and mode of death in chronic heart failure: results from the Valsartan Heart Failure Trial.

AIMS: To assess the relationship between body mass index (BMI), mortality and mode of death in chronic heart failure (CHF) patients; to define the shape of the relationship between BMI and mortality. METHODS AND RESULTS: We performed a post-hoc analysis of 5010 patients from the Valsartan Heart Failure Trial. The end-points of the study were all-cause and cardiovascular mortality. Mortality rate was 27.2% in underweight patients (BMI<22 kg/m2), 21.7% in normal weight patients (BMI 22-24.9 kg/m2), 17.9% in overweight patients (BMI 25-29.9 kg/m2) and 16.5% in obese patients (BMI>30 kg/m2) (p<0.0001). The rates of non-cardiovascular death did not differ among groups. The risk of death due to progressive heart failure was 3.4-fold higher in the underweight than in the obese patients (p<0.0001). Normal weight, overweight and obese patients had lower risk of death as compared with underweight patients (p=0.019, HR 0.76, 95% CI 0.61-0.96; p=0.0005, HR 0.68, 95% CI 0.55-0.84; p=0.003, HR 0.67, 95% CI 0.52-0.88, respectively) independently of symptoms, ventricular function, beta-blocker use, C-reactive protein and brain natriuretic peptide levels. CONCLUSIONS: In CHF patients a higher BMI is associated with a better prognosis independently of other clinical variables. The relationship between mortality and BMI is monotonically decreasing.

Calpain-mediated impairment of Na+/K+-ATPase activity during early reperfusion contributes to cell death after myocardial ischemia.

Na+ overload and secondary Ca2+ influx via Na+/Ca2+ exchanger are key mechanisms in cardiomyocyte contracture and necrosis during reperfusion. Impaired Na+/K+-ATPase activity contributes to Na+ overload, but the mechanism has not been established. Because Na+/K+-ATPase is connected to the cytoskeleton protein fodrin through ankyrin, which are substrates of calpains, we tested the hypothesis that calpain mediates Na+/K+-ATPase impairment in reperfused cardiomyocytes. In isolated rat hearts reperfused for 5 minutes after 60 minutes of ischemia, Na+/K+-ATPase activity was reduced by 80%, in parallel with loss of alpha-fodrin and ankyrin-B and detachment of alpha1 and alpha2 subunits of Na+/K+-ATPase from the membrane-cytoskeleton complex. Calpain inhibition with MDL-7943 during reperfusion prevented the loss of these proteins, increased Na+/K+-ATPase activity, attenuated lactate dehydrogenase release, and improved contractile recovery, and these beneficial effects of MDL-7943 were reverted by ouabain. The impairment of Na+/K+-ATPase was not a mere consequence of cell death because it was not altered in hearts in which contracture and cell death had been prevented by contractile blockade with 2,3-butanedione monoxime. In these hearts, concomitant calpain inhibition preserved Na+/K+-ATPase content and function and attenuated cell death occurring on withdrawal of 2,3-butanedione monoxime. In vitro assay showed no detectable degradation of Na+/K+-ATPase subunits after 10 minutes of incubation with activated calpain. Thus, we conclude that calpain activation contributes to the impairment of Na+/K+-ATPase during early reperfusion and that this effect is mainly mediated by degradation of the anchorage of Na+/K+-ATPase to the membrane cytoskeleton.

Effects of hypoxia, glucose deprivation and acidosis on phosphatidylcholine synthesis in HL-1 cardiomyocytes. CTP:phosphocholine cytidylyltransferase activity correlates with sarcolemmal disruption.

A decrease in [3H]Cho (choline) incorporation in to PtdCho (phos-phatidylcholine) preceded the onset of LDH (lactate dehydrogenase) release in HL-1 cardiomyocytes submitted to simulated ischaemia. This observation led us to examine the role of PtdCho synthesis in sarcolemmal disruption in HL-1 cardiomyocytes. To address this objective we analysed the individual effects of hypoxia, glucose deprivation and acidosis, three prominent components of ischaemia, on the different steps of the Kennedy pathway for the synthesis of PtdCho. Pulse and pulse-chase experiments with [3H]Cho, performed in whole HL-1 cells submitted to hypoxia or normoxia, in the presence or absence of glucose at different pHs indicated first, that CK (choline kinase) was inhibited by hypoxia and acidosis, whereas glucose deprivation exacerbated the inhibition caused by hypoxia. Second, the rate-limiting reaction in PtdCho synthesis, catalysed by CCT (CTP:phosphocholine cytidylyltransferase), was inhibited by hypoxia and glucose deprivation, but unexpectedly activated by acidosis. In cellfree system assays, acidosis inhibited both CK and CCT. In experiments performed in whole cells, the effect of acidosis was likely to be direct on CK, but indirect or intact-cell-dependent on CCT. Since hypoxia and glucose deprivation favoured membrane disruption, but acidosis prevented it, we hypothesized that the modulation of CCT could be an important determinant of cell survival. Supporting this hypothesis, we show that CCT activity in whole-cell experiments clearly correlated with LDH release, but not with ATP concentration. Altogether our results suggest a significant role for CCT activity in sarcolemmal disruption during ischaemia.

Effect of clinical variables on the correlation between amount of ST elevation and myocardial scintigraphic perfusion defect during coronary occlusion.

PURPOSE: We investigated if the correlation between the amount of ST elevation (STE) and myocardial ischemia could be altered by variables such as hypertension or body mass index (BMI). METHODS: A 12-lead electrocardiogram and a technetium-99m tetrofosmin injection were performed during balloon coronary occlusion in 34 patients with single-vessel disease. RESULTS: The sum of STE correlated with scintigraphic extent of ischemia (r = 0.441; P = .009), but this correlation improved significantly in men and patients with BMI of 28 kg/m2 or less and was highest in nonhypertensive patients (r = 0.763; P < .001). In contrast, it was poor in women and patients with BMI greater than 28 kg/m2 or arterial hypertension, being lowest in the latter subset (r = 0.110; P = .664). Moreover, 8 (80%) of 10 patients with extensive hypoperfusion but with low SigmaSTE (< or =20 mm) were hypertensive. CONCLUSIONS: If confirmed by larger studies, electrocardiographic underestimation of transmural ischemia during coronary occlusion in patients with hypertension or increased BMI may lead to adjustments in STE criteria for reperfusion therapy.

Ischemic preconditioning prevents calpain-mediated impairment of Na+/K+-ATPase activity during early reperfusion.

OBJECTIVES: We previously demonstrated that ischemic preconditioning (IPC) attenuates calpain activation during reperfusion. Herein, we tested the hypothesis that enhancement of Na+/K+-ATPase activity during early reperfusion as a result of calpain inhibition is involved in the protection afforded by myocardial IPC. METHODS: Intracellular Na+ concentration ([Na+]i) measured using 23Na-magnetic resonance spectroscopy, Na+/K+-ATPase activity, detachment of Na+/K+-ATPase alpha subunits from the membrane cytoskeleton, degradation of fodrin and ankyrin, and calpain activation were analysed in isolated rat hearts reperfused after 60 min of ischemia with or without previous IPC and different treatments aimed to mimic or blunt the effects of IPC. RESULTS: In non-treated hearts subjected to ischemia (control hearts), reperfusion for 5 min severely reduced Na+/K+-ATPase activity and dissociated alpha1 and alpha2 subunits of Na+/K+-ATPase from the membrane-cytoskeleton complex in parallel with proteolysis of alpha-fodrin and ankyrin-B and calpain activation. IPC accelerated the recovery of [Na+]i, increased Na+/K+-ATPase activity, and prevented dissociation of Na+/K+-ATPase from the membrane-cytoskeleton complex. IPC also prevented alpha-fodrin and ankyrin-B loss and calpain activation, effects that were associated with attenuated lactate dehydrogenase (LDH) release and infarct size and improved contractile recovery. These effects of IPC were reproduced by perfusing the hearts with the calpain inhibitor MDL-28170 and by transient stimulation of cAMP-dependent protein kinase (PKA) with CPT-cAMP, and they were reverted by perfusing with the PKA inhibitor H89. CONCLUSION: The results of the present study are consistent with the hypothesis that enhanced recovery of Na+/K+-ATPase activity during reperfusion as a result of attenuated calpain-mediated detachment of the protein from the membrane-cytoskeleton complex contributes to the protection afforded by IPC.

Mitochondrial Ca2+ uptake during simulated ischemia does not affect permeability transition pore opening upon simulated reperfusion.

OBJECTIVE: Reenergization of ischemic cardiomyocytes may be associated with acute necrotic cell death due in part to cytosolic Ca2+ overload and opening of a permeability transition pore (PTP) in mitochondria. It has been suggested that Ca2+ overload during ischemia primes mitochondria for PTP opening during reperfusion. We investigated the ability of mitochondria to uptake Ca2+ during simulated ischemia (SI) and whether this uptake determines PTP opening and cell death upon simulated reperfusion (SR). METHODS: Rat heart mitochondria were submitted to either hypoxia (anoxic chamber) or to SI (respiratory inhibition, substrate depletion and acidosis) and subsequent SR. Mitochondrial Ca2+ uptake was monitored using Ca2+ microelectrodes after exposure to different [Ca2+] up to 25 microM during SI, and PTP opening was assessed by quantification of mitochondrial swelling (changes in absorbance rate at 540 nm) and calcein release. Mitochondrial Ca2+ uptake (Rhod-2 fluorescence) and cytosolic Ca2+ rise (Fura-2 ratio fluorescence) were further investigated in HL-1 cardiac myocytes submitted to SI/SR, and the effect of reducing mitochondrial Ca2+ load (with 25 microM ruthenium red) or blocking PTP opening (with 0.5 microM cyclosporin A) on the rate of cell death was investigated in adult cardiomyocytes exposed to SI/SR. RESULTS: SI induced a progressive dissipation of mitochondrial membrane potential (TMRE fluorescence); however, prior to the completion of depolarization, high levels of Ca2+ uptake were observed in mitochondria. SR induced PTP opening but this phenomenon was not influenced by the magnitude of mitochondrial Ca2+ uptake during previous SI. Blockade of the mitochondrial Ca2+ uniporter during SI in cardiomyocytes attenuated mitochondrial Ca2+ uptake but increased cytosolic Ca2+ overload and cell death upon subsequent SR. CONCLUSION: Mitochondrial Ca2+ uptake during SI buffers cytosolic Ca2+ overload but its magnitude appears not to be an important determinant of PTP opening upon subsequent SR.

Antagonism of selectin function attenuates microvascular platelet deposition and platelet-mediated myocardial injury after transient ischemia.

OBJECTIVES: The goal of this study was to assess whether selectin blockade reduces myocardial platelet deposition and platelet-mediated injury after transient ischemia. BACKGROUND: Selectins participate in platelet adhesion to reperfused endothelium. METHODS: Thiopental-anesthetized, open-chest pigs were subjected to mechanical injury of the left anterior descending coronary artery followed by a 48-min occlusion and 2 (n = 20) or 4 (n = 16) h of reperfusion. Fifteen minutes before occlusion, animals were blindly allocated to receive a continuous intravenous infusion of the selectin blocker fucoidan (30 microg/kg/min, plus a 1-mg/kg bolus in the latter group) or saline. In isolated rat hearts infused with thrombin-activated platelets, the effects of fucoidan (30 microg/ml) administered during reperfusion after 40 min of global ischemia were also analyzed. RESULTS: Fucoidan did not prevent the development of cyclic reductions in coronary flow, but reduced the content of (99m)Tc-labeled platelets in reperfused myocardium after 2 h of reperfusion (23.4 +/- 3.3 vs. 42.1 +/- 8.3 x 10(6) platelets/g in treated and untreated animals, p = 0.03) and attenuated the impairment in the coronary flow reserve and reduced infarct size after 4 h (53 +/- 2% vs. 73 +/- 5% of the ischemic region, respectively, p = 0.003). Treated animals showed a trend toward less neutrophil infiltration early after reperfusion, but not after 4 h. In isolated hearts, fucoidan improved functional recovery and reduced coronary resistance and lactate dehydrogenase release, lacking any beneficial effects if given in the absence of platelets. CONCLUSIONS: The results suggest that selectin-dependent adhesion is a prominent mechanism of platelet deposition in reperfused cardiac microvessels and highlight its potential as a therapeutic target in patients with acute myocardial infarction.

Membrane association of nitric oxide-sensitive guanylyl cyclase in cardiomyocytes.

OBJECTIVE: Although the importance of the cyclic GMP (cGMP) signaling pathway in cardiac myocytes is well established, little is known about its regulation. Ca2+-dependent translocation of nitric oxide (NO) sensitive guanylyl cyclase (GCNO) to the cell membrane has been recently proposed to play a role. The aim of this study was to determine the possible functional relevance of GCNO bound to the cardiomyocyte membrane. METHODS: Cytosolic and particulate fractions of adult rat cardiomyocytes were isolated and blotted, and their GCNO activity was assayed in parallel experiments. RESULTS: In untreated cardiomyocytes, approximately 30% of beta1-and alpha1-subunits of GCNO and a similar proportion of GCNO activity were found in the particulate fraction. The dependence of GCNO activity on pH, Ca2+, GTP and NO donor concentrations was similar in particulate and cytosolic fractions. Treatment of cardiomyocytes with the ionophore A23187 caused GCNO to translocate to the sarcolemma, increased GCNO activity in this fraction, and potentiated NO-mediated cGMP synthesis. These effects appeared to be mediated by Ca2+-dependent changes on the phosphorylation status of GCNO, since they were enhanced by the non-selective inhibitor staurosporine and by the selective inhibitor of Ca2+/calmodulin-dependent protein kinase KN-93. The effect of drugs increasing intracellular Ca2+ on cGMP synthesis was clearly correlated with their effects on membrane-associated GCNO activity but not with their effects on cytosol-associated GCNO. CONCLUSION: These results are the first evidence that 1) GCNO is associated with the cell membrane in cardiomyocytes, 2) the regulation of membrane-associated GCNO differs from that of cytosolic GCNO, and 3) membrane association may have a crucial role in determining the response of cells to NO.

Prognostic value of lead aVR in patients with a first non-ST-segment elevation acute myocardial infarction.

BACKGROUND: ST-segment elevation in lead aVR has been associated with severe coronary artery lesions in patients with acute coronary syndromes, but the prognostic significance of this finding is unknown. METHODS AND RESULTS: We analyzed the initial ECG in 775 consecutive patients admitted to our center with a first acute myocardial infarction without ST-segment elevation in leads other than aVR or V1. The rates of in-hospital death in patients without (n=525) and with 0.05 to 0.1 mV (n=116) or > or =0.1 mV (n=134) of ST-segment elevation in lead aVR were 1.3%, 8.6%, and 19.4%, respectively (P<0.001). After adjustment for the baseline clinical predictors and for ST-segment depression on admission, the odds ratios for death in the last 2 groups were, respectively, 4.2 (95% CI, 1.5 to 12.2) and 6.6 (95% CI, 2.5 to 17.6). The rates of recurrent ischemic events and heart failure during hospital stay also increased in a stepwise fashion among the groups, whereas creatine kinase-MB levels were similar. Among the 437 patients that were catheterized within 6 months, the prevalence of left main or 3-vessel coronary artery disease in the 3 groups was 22.0%, 42.6%, and 66.3%, respectively (P<0.001). CONCLUSIONS: Lead aVR contains important short-term prognostic information in patients with a first non-ST-segment elevation acute myocardial infarction. Because the poorer outcome predicted by ST-segment elevation in lead aVR seems to be related to a more severe coronary artery disease, an early invasive approach might be especially beneficial in patients presenting with this finding.

Long-term follow-up of aortic intramural hematoma: predictors of outcome.

BACKGROUND: Aortic intramural hematoma (IMH) evolves very dynamically in the short-term to regression, dissection, or aortic rupture. The aim of the present study was to assess the long-term clinical and morphological evolution of medically treated IMH. METHODS AND RESULTS: Fifty of 68 consecutive patients with aortic IMH monitored clinically and by imaging techniques at 3, 6, and 12 months and annually thereafter were prospectively studied. Mean follow-up was 45+/-31 months. In the first 6 months, total IMH regression was observed in 14 and progression to aortic dissection in 18 patients; in 14 of these, the dissection was localized, and 12 later developed pseudoaneurysm. At the end of follow-up, the IMH had regressed completely without dilatation in 17 patients (34%), progressed to classical dissection in 6 (12%), evolved to fusiform aneurysm in 11 (22%), evolved to saccular aneurysm in 4 (8%), and evolved to pseudoaneurysm in 12 (24%). Evolution to dissection was related to echolucency (P<0.02) and to longitudinal extension of IMH (P<0.01). Multivariate analysis showed an independent association between regression and smaller maximum aortic diameter and between aneurysm formation and atherosclerotic ulcerated plaque and absence of echolucent areas in IMH. CONCLUSIONS: The most frequent long-term evolution of IMH is to aortic aneurysm or pseudoaneurysm. Complete regression without changes in aorta size is observed in one third of cases, and progression to classical dissection is less common. A normal aortic diameter in the acute phase is the best predictor of IMH regression without complications, and absence of echolucent areas and atherosclerotic ulcerated plaque are associated with evolution to aortic aneurysm.

Effect of long-acting nifedipine on mortality and cardiovascular morbidity in patients with stable angina requiring treatment (ACTION trial): randomised controlled trial.

BACKGROUND: Calcium antagonists are widely prescribed for angina pectoris but their effect on clinical outcome is controversial. We aimed to investigate the effect of the calcium antagonist nifedipine on long-term outcome in patients with stable angina pectoris. METHODS: We randomly assigned 3825 patients with treated stable symptomatic coronary disease to double-blind addition of nifedipine GITS (gastrointestinal therapeutic system) 60 mg once daily and 3840 to placebo. The primary endpoint was the combination of death, acute myocardial infarction, refractory angina, new overt heart failure, debilitating stroke, and peripheral revascularisation. Mean follow-up was 4.9 years (SD 1.1). Analysis was by intention to treat. FINDINGS: 310 patients allocated nifedipine died (1.64 per 100 patient-years) compared with 291 people allocated placebo (1.53 per 100 patient-years; hazard ratio 1.07 [95% CI 0.91-1.25], p=0.41). Primary endpoint rates were 4.60 per 100 patient-years for nifedipine and 4.75 per 100 patient-years for placebo (0.97 [0.88-1.07], p=0.54). With nifedipine, rate of death and any cardiovascular event or procedure was 9.32 per 100 patient-years versus 10.50 per 100 patient-years for placebo (0.89 [0.83-0.95], p=0.0012). The difference was mainly attributable to a reduction in the need for coronary angiography and interventions in patients assigned nifedipine, despite an increase in peripheral revascularisation. Nifedipine had no effect on the rate of myocardial infarction. INTERPRETATION: Addition of nifedipine GITS to conventional treatment of angina pectoris has no effect on major cardiovascular event-free survival. Nifedipine GITS is safe and reduces the need for coronary angiography and interventions.

Lack of effect of glycoprotein IIb/IIIa blockade on myocardial platelet or polymorphonuclear leukocyte accumulation and on infarct size after transient coronary occlusion in pigs.

OBJECTIVES: We sought to assess the effect of glycoprotein (GP) IIb/IIIa blockade on myocardial platelet and polymorphonuclear leukocyte accumulation and on infarct size after coronary injury and transient coronary occlusion (CO) in pigs. BACKGROUND: It has been suggested that platelet GP IIb/IIIa blockade might reduce the severity of microvascular damage after reperfusion. METHODS: Sixteen thiopental-anesthetized, open-chest pigs, in whom platelets had been labeled with technetium-99m (99mTc) on the previous day, were submitted to catheter-induced left anterior descending coronary artery (LAD) injury followed by 55 min of CO and 5 h of reperfusion. Five minutes before reflow, the animals were blindly allocated to receive lamifiban (intravenous bolus of 250 microg/kg body weight and continuous infusion of 3 microg/kg per min) or saline. RESULTS: Lamifiban had a rapid and potent platelet anti-aggregatory effect, as demonstrated by significant prolongation of the bleeding time and profound (approximately 90%) inhibition of ex vivo platelet aggregation, and completely prevented the development of cyclic flow reductions of the LAD (0 vs. 5 +/- 1, one of them followed by re-occlusion, in control animals, p = 0.005). However, compared with animals receiving placebo, those treated with lamifiban had a similar (p = NS) content of (99m)Tc platelets in the reperfused myocardium (288 +/- 40% vs. 205 +/- 27% of the value in the control region, respectively) and similar myeloperoxidase activity (0.50 +/- 0.17 U/g vs. 0.47 +/- 0.17 U/g, respectively) and infarct size (46.8 +/- 12.0% vs. 49.8 +/- 10.5% of the area at risk, respectively). Arteriolar platelet thromboemboli were very rarely seen on histologic analysis. Lamifiban did not modify platelet P-selectin expression in additional studies. CONCLUSIONS: Platelet GP IIb/IIIa blockade has a potent antithrombotic effect at the culprit lesion, but does not significantly reduce the magnitude of microvascular platelet accumulation or myocardial damage after transient CO.

Relation of myocardial perfusion defects and nonsignificant coronary lesions by angiography with insights from intravascular ultrasound and coronary pressure measurements.

Several studies have demonstrated a correlation between myocardial ischemia and severity of coronary lesions as determined by intravascular ultrasound (IVUS) and fractional flow reserve (FFR) measurements. However, their value for the assessment of mild coronary stenoses that are associated with myocardial perfusion abnormalities has not been well studied. The objective of this study was to prospectively compare the results of myocardial perfusion as determined by exercise/dipyridamole myocardial single-photon emission computed tomography with IVUS and FFR measurements in patients who had angiographically mild coronary stenosis (< 50% diameter stenosis by quantitative coronary angiography). Forty-eight patients who had stable coronary disease (61 +/- 11 years of age; 6 women) were included. All had mild coronary stenosis in the proximal/middle segment of > or = 1 coronary artery and had undergone maximal exercise myocardial technetium-99m tetrofosmin single-photon emission computed tomography within 48 hours before coronary angiography. IVUS measurements included lesion lumen area, external elastic membrane area, lesion plaque burden (calculated as external elastic membrane minus lumen area, divided by external elastic membrane, and multiplied by 100), and lumen area stenosis (calculated as reference lumen area minus lesion lumen area, divided by reference lumen area, multiplied by 100). Fifty-three coronary lesions were studied, with a mean percent diameter stenosis of 34.9 +/- 7.9% on angiography. Myocardial perfusion defects were demonstrated by single-photon emission computed tomography in 11 patients (12 myocardial regions) with no differences in lesion percent diameter stenosis compared with those without perfusion defects. The presence of reversible perfusion defects was associated with a higher lesion plaque burden as evaluated by IVUS (67.4 +/- 8.1% vs 60.2 +/- 9.3%, p = 0.01). FFR values did not differ in the presence or absence of perfusion defects (0.90 +/- 0.06 vs 0.92 +/- 0.07, respectively; p = NS). In conclusion, plaque burden as determined by IVUS may partly explain the presence of myocardial perfusion defects in cases of angiographically nonsignificant coronary lesions. However, the high FFR values associated with these lesions suggest that other mechanisms, such as endothelial/microvascular dysfunction, might also account for perfusion abnormalities in these patients.

Clinical and neurohumoral consequences of diuretic withdrawal in patients with chronic, stabilized heart failure and systolic dysfunction.

BACKGROUND: Loop diuretics are beneficial in heart failure in the short term because they eliminate fluid retention, but in the long-term, they could adversely influence prognosis due to activation of neurohumoral mechanisms. AIMS: To explore the changes induced by diuretic withdrawal in chronic nonadvanced heart failure. METHODS: Diuretics were withdrawn in 26 stabilized heart failure patients with systolic dysfunction (ejection fraction [EF]<45%). Clinical status was evaluated by physical exam, exercise capacity (corridor test) and New York Heart Association (NYHA) class. Biochemical and neurohumoral determinations were performed at baseline and at 3 months. RESULTS: At 3 months, 17 out of 26 patients (65%) were able to tolerate diuretic interruption without a deterioration in exercise capacity or New York Heart Association functional class. Renal function parameters improved (baseline urea 46.2+/-10.8 to 39.2+/-10.1 mg/dl at 3 months, p=0.014; creatinine 1.1+/-0.23 to 0.98+/-0.2 mg/dl, p=0.013). Glucose metabolism also improved (fasting glucose 151+/-91 to 122+/-14 mg/dl, p=0.035). Heart rate and systolic blood pressure did not significantly change, while diastolic blood pressure increased (from 80+/-10 to 87+/-13 mm Hg, p=0.006). Neurohumoral determinations showed a decrease in plasma renin activity (4.19+/-5.96 to 2.88+/-4.98 ng/ml, p=0.026), with no changes in aldosterone, arginine-vasopressin, endothelin-1 and norepinephrine. In contrast, atrial natriuretic peptide significantly increased (115+/-87 to 168+/-155 pg/ml, p=0.004). CONCLUSION: Diuretic withdrawal in stabilized heart failure with systolic dysfunction is associated with an improvement in renal function parameters, glucose metabolism and some neurohumoral parameters, such as plasma renin activity; however, atrial natriuretic peptide levels increased.