Selective pacing sites.

he right ventricular apex (RVA) has always been the most used pacing site, because it is easily accessible and provides a stable lead position with a low dislodgment rate. However, it is well-known that long-term right ventricular apical pacing may have deleterious effects on left ventricular function by inducing a iatrogenic left bundle branch block, which can have strong influences on the left ventricle hemodynamic performances. More specifically, RVA pacing causes abnormal contraction patterns and the consequent dyssynchrony may cause myocardial perfusion defects, histopathological alterations, left ventricular dilation and both systolic and diastolic left ventricular dysfunction. All these long-term changes could account for the higher morbidity and mortality rates observe in patients with chronic RVA pacing compared with atrial pacing. This observation led to the reassessment of traditional approaches and to the research of alternative pacing sites, in order to get to more physiological pattern of ventricular activation and to avoid deleterious effects. Then, attempts were made with: right ventricular outflow tract (RVOT) pacing, direct His bundle pacing (DHBP), parahisian pacing (PHP) and bifocal (RVA + RVOT) pacing. For example, RVOT pacing, especially in its septal portion, is superior to the RVA pacing and it would determine a contraction pattern very similar to the spontaneous one, not only because the septal portions are the first parts to became depolarized, but also for the proximity to the normal conduction system. RVOT is preferable in terms of safety too. DHBP is an attractive alternative to RVA pacing because it leads to a synchronous depolarization of myocardial cells and, therefore, to an efficient ventricular contraction. So it would be the best technique, however the procedure requires longer average implant times and dedicated instruments and it cannot be carried out in patients affected by His bundle pathologies; furthermore, due to the His bundle fibrous area, higher pacing thresholds are required, causing accelerated battery depletion. For all these reasons, PHP could be considered an important alternative to DHBP, to be used on a large scale. Finally, bifocal pacing in CRT candidates, provides better acute hemodynamic performance than RVA pacing, derived from a minor intra- and interventricular dyssynchrony, expressed also by the QRS shortening. Then, bifocal pacing could be taken into account when RVA pacing is likely to be the origin of serious mechanical and electrical dyssynchrony or when CRT is contraindicated or technically impossible. So, whatever chosen as selective pacing site, you must look also at safety, effectiveness and necessary equipment for an optimal pacing site.

ST segment elevations: always a marker of acute myocardial infarction?

Chest pain is one of the chief presenting complaints among patients attending Emergency department. The diagnosis of acute myocardial infarction may be a challenge. Various tools such as anamnesis, blood sample (with evaluation of markers of myocardial necrosis), ultrasound techniques and coronary computed tomography could be useful. However, the interpretation of electrocardiograms of these patients may be a real concern. The earliest manifestations of myocardial ischemia typically interest T waves and ST segment. Despite the high sensitivity, ST segment deviation has however poor specificity since it may be observed in many other cardiac and non-cardiac conditions. Therefore, when ST-T abnormalities are detected the physicians should take into account many other parameters (such as risk factors, symptoms and anamnesis) and all the other differential diagnoses. The aim of our review is to overview of the main conditions that may mimic a ST segment Elevation Myocardial Infarction (STEMI).

Prevalence of metabolic syndrome: a comparative analysis in an unselected sample of mediterranean subjects.

AIM: The metabolic syndrome (MS) is associated with increased cardiovascular and cerebrovascular risk. This study aimed to compare the difference of the three established diagnostic criteria of MS, developed by Adult Treatment Panel III (ATP III), American Heart Association (AHA) and National Heart Lung and Blood Institute (NHLBI), and International Diabetes Federation (IDF), with regard to the prevalence of the syndrome and the ability to correctly identify individuals with cardiovascular or cerebrovascular disease or subclinical atherosclerosis. METHODS: We studied 947 consecutive patients underwent clinical evaluation between the 1997-2002. The project design included a medical assessment, biochemical analyses and the ecocolordoppler examination of carotid arteries. RESULTS: The MS prevalence was 37% in ATPIII subjects, 36% in AHA/NHLBI subjects and 43% in IDF subjects. Excluding patients with diabetes (N.=259), the MS prevalence ranged from 32% (ATPIII and AHA/NHLBI subjects) and 40% (IDF subjects). By most criteria, MS-positive subjects had significant incidence of carotid atherosclerosis (P<0.05) and cardiovascular events (P<0.05) than MS-negative subjects, but not cerebrovascular events. Finally, patients with MS had higher serum levels of fibrinogen (P<0.04). CONCLUSION: Subclinical atherosclerosis and cardiovascular events were increased in presence of the MS, irrespective of the several definitions.

Vasospastic angina and scombroid syndrome: a case report.

Scombroid syndrome is a fish poisoning characterised by the onset of symptoms compatible with a pseudoallergic reaction; it is rarely also responsible of signs and symptoms of acute coronary syndromes, as demonstrated in this case report.

Metabolic syndrome (MetS) predicts cardio and cerebrovascular events in a twenty years follow-up. A prospective study.

BACKGROUND AND PURPOSE: Metabolic syndrome (MetS) is a cluster of cardiovascular risk factors, considered as emerging and promoting atherosclerosis. This study aimed at the evaluation of the influence of MetS on the prediction of cerebro and cardiovascular events during a 20 years follow-up period in an asymptomatic population of middle-aged subjects. METHODS: We evaluated 529 asymptomatic persons through a prospective study. Study population was divided into two subgroups: patients with and without MetS. Echo-color-Doppler was used in order to assess the presence of subclinical atherosclerosis. A 20 years follow-up study was carried out in order to estimate the incidence of cerebro and cardiovascular, fatal and non fatal, events (AMI, stroke, abdominal aortic aneurysm, TIA, angina pectoris). RESULTS: 242 cerebro and cardiovascular events were registered, 43 fatal (24 in MetS and 19 in controls) and 199 non fatal (120 with MetS and 79 without it, p < 0.0001). Free-events survival was lower in patients suffering from MetS (p < 0.0012; HR 0.6847; C.I.95%: 0.5274-0.8889). Ultrasound showed a higher prevalence of subclinical atherosclerosis in patients with MetS than in the unaffected ones (68.12% vs. 57.5% p < 0.01; OR = 1.58 with C.I.95% = 1.10-2.28, p < 0.01). CONCLUSIONS: Patients with MetS have a higher cardiovascular risk that can be explained by atherosclerotic changes: the components of MetS interact to affect vascular thickness synergistically and promote the development of subclinical atherosclerosis. So we recommend to prevent the development of MetS abnormalities and to investigate the presence of subclinical atherosclerosis by echo-color-Doppler in order to stratify more accurately the global CV risk.

Prediction of vascular events in subjects with subclinical atherosclerosis and the metabolic syndrome: the role of markers of inflammation.

AIM: The presence of the metabolic syndrome (MS) increases cardiovascular morbidity and mortality and we aimed to assess the outcome in subjects with the MS and subclinical atherosclerosis. METHODS: We followed-up for five years 339 Mediterranean subjects with asymptomatic carotid intima-media thickness >0.9 mm (men: 60%; age: 66±5 years), of whom 130 had the MS (men: 59%; age: 66±5 years), evaluating at baseline traditional cardiovascular risk factors (including male gender, older age, obesity, hypertension, diabetes, smoking, family history of cardiovascular diseases, dyslipidemia) and plasma levels of C-reactive protein and fibrinogen. RESULTS: Cardio- and cerebrovascular events were registered in the 29% of subjects with the MS and in the 20% of those without it and the presence of more criteria for the diagnosis of the MS was significantly associated with vascular morbidity and mortality. By multivariate analysis, including all baseline variables, independent predictive roles for the events were found for elevated markers of inflammation (OR 3.8), elevated fasting glucose (OR 2.1) and elevated triglycerides (OR 1.4). CONCLUSION: These findings confirm a worst vascular outcome in subjects with more criteria for the diagnosis of the MS and further suggest the need of future research to understand the combined role of inflammation and the MS in the progression from subclinical to clinical atherosclerosis.

Marshall's vein persistence: a rare and occasional finding during pacemaker implantation.

In adults the oblique vein of Marshall is usually absent or very thin, and it is hard to be found. In this case report we describe a case of persistence observed during pacemaker implantation.

Medical therapy for patients with subclinical and clinical carotid atherosclerosis.

The management of carotid artery disease includes both modifications in life style as well treatment of vascular risk factors. However, strict risk factor modification, including improved antihypertensive therapy, lipid management, smoking cessation, and antiplatelet therapy, promise for reducing the vascular event rate in patients with carotid atherosclerosis. The best medical management for stroke prevention was highlighted in clinical practice guidelines issued jointly in 2006 by the American Heart Association and the American Stroke Association, and co-sponsored by the Council on Cardiovascular Radiology and Intervention and the American Academy of Neurology. Lowering blood pressure to a target below 120/80 mm Hg by life style interventions and antihypertensive treatment. Glucose control to near-normoglycemic levels (target hemoglobin A1C ≤7%) is recommended among diabetics to reduce micro-vascular complications and, with lesser certainty, macrovascular complications. The primary objective of this review is to summarize the current evidence and standards for the advanced diagnostic and management strategies used in asymptomatic and symptomatic patients with carotid atherosclerosis.

Graft patency and late outcomes for patients with ST-segment elevation myocardial infarction who underwent coronary surgery.

OBJECTIVE: The aim of our study was to assess the long-term clinical outcomes and the grafts patency rates of patients with ST-segment elevation myocardial infarction (STEMI) who underwent urgent or emergency coronary artery bypass grafting (CABG). MATERIALS: Participants in two previous studies comprising 207 STEMI patients undergoing on-pump (145 patients) or off-pump (62 patients) coronary artery bypass graft (CABG) surgery in our institution were prospectively followed to assess late mortality, graft patency, and major adverse cardiac-related event (MACE) rates. Graft patency was evaluated by multi-detector computed tomography angiography 64-slice scan. Mean times of graft implantation were 38±16 months and 37±14 months in on-pump and off-pump, respectively. Follow-up data were obtained in all patients and was 100% complete. RESULTS: Late mortality rate was 7.4% (10 patients) in the on-pump and 6.5% (4 patients) in off-pump groups (p=0.45). Five-year overall survival rate (±SE) was 93.5±2.1% and 92.6±1.9% in the off-pump vs on-pump, respectively. Five years' freedom from cardiac-related death was 94.9±2.9% in the on-pump group vs 96.8±3.2% in the off-pump group (p=0.25). Five years' freedom from cardiac-related events was 89.7±1.6% in the on-pump group versus 93.5±1.8% in the off-pump group (p=0.32). In all patients, a total of 449/491 (91.5%) grafts were patent. Percentages of overall grafts classified as patent were similar in the on-pump group (90.7% - 322/355 conduits) versus the off-pump group (91% - 133/146 conduits). Graft patency rates were also similar between the two groups with regard to arterial and saphenous vein conduits, and with regard to different branches of the coronary arteries grafted. CONCLUSION: Our data suggest that off-pump CABG patients have the same late mortality, MACEs, and graft patency rates as conventional cardioplegic cardiac arrest CABG patients. In our opinion, urgent or emergency CABG for patients with STEMI can be done either way.

Cardiac risk stratification in elective non-cardiac surgery: role of NT-proBNP.

AIM: The aim of the study was to investigate the utility of NT-proBNP measurement for the stratification of presurgical cardiac risk. METHODS: Cardiac risk before elective non-cardiac surgery was evaluated in 82 consecutive patients. From each patient a venous blood sample was drawn to determinate NT-proBNP levels. Patients were followed up over three months in order to detect the occurrence of cardiac adverse events. RESULTS: NT-proBNP was positively correlated (P<0.0001) with age, days of hospitalization (P=0.001) and ASA class (P=0.001). High surgical risk (P<0.0001), diabetes (P=0.004), dyslipidemia (P=0.006) and elevated levels of NT-proBNP (P<0.0001) were significantly correlated with events. Using a logistic regression analysis we found an independent association between pre-operative elevated NT-proBNP and postoperative cardiac events (OR 1.2, 95% CI 1.0-1.4, P=0.01). CONCLUSION: Measuring NT-proBNP before non cardiac surgery in clinical practice could be useful to better stratify patients' risk.

Agenesis of the renal segment of inferior vena cava associated with venous stasis.

Congenital anomalies of the inferior vena cava is an extremely rare vascular anomaly with controversial pathogenesis. Anomalies of the inferior vena cava (IVC) are present in 0.3% to 0.5% of otherwise healthy individual and in 0.6% to 2% of patients with other cardiovascular defects. The phenomenon of absence of the IVC has been described in a variety of ways such as absence, agenesis, anomalous, and interruption of a particular segment ([infra] hepatic, prerenal, renal, or infrarenal) of the IVC. We describe a 42-year-old man with chronic venous insufficiency, without DVT, caused by congenital absence of renal segment of the IVC.

Carotid intimal-media thickness and endothelial function in young patients with history of myocardial infarction.

AIM: The aim of the study was to evaluate the prevalence of carotid atherosclerosis and endothelial dysfunction in 45 young patients (38 mens and 7 females) with myocardial infarction (MI), age 29-45, mean age 42+/-3 years, to verify its possible role as a marker of coronary atherosclerosis. METHODS: Vascular echography was performed to verify the presence of carotid atherosclerosis and/or endothelial dysfunction in 45 young patients with MI and in 45 healthy control subjects well matched for age and sex. RESULTS: We observed a normal intima media thickness (IMT) only in 30% of patients with juvenile myocardial infarction (JMI) compared with 66% in the control group (P<0.0001) and 34% of patients showed an increased IMT compared with 24% of healthy subjects (P<0.0001). Compared with control subjects, patients with JMI had lower flow-mediated reactivity of the brachial arteries (P<0.05). There was a negative linear relationship between flow-mediated dilation and IMT (P<0.001). The severity of coronary artery disease (CAD) was correlated with increased IMT and with a lower flow-mediated dilation. Finally, multiple regression analysis, demonstrated that both brachial-artery reactivity and carotid IMT were significantly and independently correlated with severity of CAD. CONCLUSIONS: Structural (carotid atherosclerosis) and functional changes (endothelial dysfunction) were present at an early age in the arteries of persons with history of JMI.

Atrial fibrillation and mild cognitive impairment: what correlation?

AIM: Atrial fibrillation (AF), in addition to macroembolic complications, may also produce multiple cerebral ischemic areas due to microembolic phenomena and transient hypoperfusion, eventually leading to a progressive cognitive impairment and even to acclaimed vascular dementia. The aim of this study was to evaluate the prevalence of cognitive impairment in patients with AF. The reported results concern data obtained at the moment of recruitment. METHODS: The authors studied 42 patients with a history of non valvular AF (paroxysmal, persistent, recurrent or permanent) and 40 homogenous controls in sinus rhythm without previous AF. All subjects underwent anamnesis, physical examination, biochemical and instrumental tests. To investigate the cognitive status, subjects underwent the following neuropsychological rating scales: Mini Mental State Examination (MMSE), Clinical Dementia Rating Scale (CDR),Activity of Daily Living (ADL), Instrumental Activity of Daily Living (IADL) Global Deterioration Scale (GLDS), Geriatric Depression Scale (GDS) and Hachinski Ischemic Score (HIS). RESULTS: AF Patients had worse scores versus controls at GLDS (P=0.0001), HIS (P=0.001), CDR (P=0.07) and GDS (P=0.07); no significant differences were found for MMSE even after correction for age and education. AF patients treated with warfarin showed better scores at CDR (P=0.04),GLDS (P=0.03) and GDS (P=0.007), compared to those in aspirin-treatment. Corrected MMSE scores did not differ. CONCLUSIONS: The authors identified a slight cognitive impairment in the AF group; patients with paroxysmal, persistent or recurrent AF showed worse cognitive performances than permanent ones, suggesting a possible microembolic pathogenesis. Anticoagulation therapy could play a protective role, however more evidence is needed.

The predictive role of C-reactive protein in patients with hypertension and subclinical atherosclerosis.

BACKGROUND: Recent guidelines published by the joint European Society of Hypertension/European Society of Cardiology have suggested the inclusion of C-reactive protein (CRP) in the standard assessment of cardiovascular risk in hypertensive patients, but few data are available on the role of CRP in patients with carotid lesions. METHODS: We studied 472 patients, 236 with and 236 without hypertension, sex- and age-matched, with and without early stages of atherosclerosis (e.g. those with an asymptomatic intima-media thickness of >0.9 mm), the influence of all the other traditional cardiovascular risk factors (e.g. older age, male sex, obesity, diabetes, smoking habit, family history of coronary artery disease, dyslipidaemia) and of high-sensitivity CRP levels on cerebrovascular and cardiovascular events in a 5-year follow up. RESULTS: At the end of follow up, patients with hypertension had more events than those without (25% vs 17%, P < 0.05). Proportional hazard analysis revealed in the group of patients without hypertension the presence of baseline carotid lesions (P= 0.02) as predictor of events. In patients with hypertension, the presence of baseline carotid lesions (P= 0.04) and elevated CRP levels (P= 0.02) predicted clinical events. Patients with hypertension also showed a significant relationship between clinical events and quintiles of CRP levels (P < 0.01). CONCLUSION: Beyond the utility of high-sensitivity CRP levels in the prediction of early and late stages of atherosclerosis and subsequently on its association with clinical events, the therapeutic implications of these results remain to be evaluated by further studies.

Short term prognostic role of NT-proBNP in patients after myocardial infarction.

AIM: The clinical and prognostic role of cardiac natriuretic peptides (CNP) in patients with heart failure is well known; recently, several studies have evaluated the possibility of using CNP to evaluate their potential prognostic role in patients with acute coronary syndromes (ACS). The aim of this study was to evaluate the short term prognostic value of NT-proBNP in 70 patients admitted for ACS. METHODS: The authors studied 70 patients with ACS, evaluating, at admission, clinical-anamnestic, instrumental and laboratory characteristics including NT-proBNP plasma levels. Patients were monitored in a 6-month-follow-up to record adverse fatal events and their possible correlation with baseline characteristics. RESULTS: The incidence of adverse events during the follow-up period was 28% (10 patients). In patients with adverse events, the authors observed lower left ventricle ejection fraction (P=0.01), higher prevalence of ST elevation myocardial infarction (P=0.03) and higher NT-proBNP levels (P=0.03), compared to those without adverse events. Moreover, the logistic regression analysis underlined how ST elevation myocardial infarction (P=0.05) and higher NT-proBNP levels (P=0.05) were the only predictive variables for adverse events during the follow up period. CONCLUSIONS: This study demonstrates the short term prognostic role of NT-pro BNP in patients admitted for ACS.

Prognostic role of endothelial dysfunction and carotid intima-media thickness in patients undergoing coronary stent implantation.

AIM: Impaired endothelial function and increased carotid intima-media thickness are key events in the atherosclerotic process and predict future cardiovascular events in subjects with and without coronary artery disease. The purpose of this study was to investigate whether the vasodilator response to increased flow in the brachial artery and the presence of carotid lesions may have a prognostic significance for in-stent restenosis in patients undergoing coronary angioplasty. METHODS: The study population included 58 patients undergoing percutaneous coronary intervention (PCI) with stenting and at least 10 months of follow-up. All patients underwent ultrasound detection of brachial artery reactivity 30 days after PCI. Flow mediated dilatation (FMD) was investigated after 5 minutes of occlusion of the artery and nitroglycerin mediated dilation (NMD) was investigated after administration of sublingual nitrates. Vascular echography was performed to measure intima media thickness (IMT) of carotid arteries. At baseline we evaluated all the established traditional cardiovascular risk factors. We also subdivided our study cohort according to values of FMD in patients with FMD above and patients below the median value. RESULTS: Patients with FMD above the median value showed higher prevalence of hypertension (P=0.002), diabetes (P=0.02) and carotid IMT (P=0.006) than those below the median. Brachial FMD was inversely correlated (P=0.001) to carotid IMT. At the end of follow-up clinical events occurred in nine patients. In a multivariate analysis, including all the variables evaluated at baseline, carotid IMT (P=0.02), level of glycemia (P=0.001), a lower FMD (P=0.005) and presence of carotid plaque remained the only variables predictive of restenosis. CONCLUSIONS: Evaluation of FMD and carotid IMT may provide important prognostic information in patients undergoing PCI.