How to adapt the implantation technique for the new SAPIEN 3 transcatheter heart valve design

The new balloon-expandable Edwards SAPIEN 3 THV has significant design improvements requiring adjustments in the implantation technique as compared to the previous generation SAPIEN XT. Basically, the new valve requires less oversizing due to the outer skirt, which, if positioned underneath the annulus, can reduce the occurrence and severity of paravalvular leak (PVL). As with any transcatheter vale, a thorough assessment of the device-landing-zone, the surrounding structures, and the distribution of calcifications is of vast importance. Once the SAPIEN 3 valve is positioned with the initial orientation of the middle balloon marker at the level of the leaflet hinge points, the outer skirt will remain under the annulus, despite the foreshortening of the lower inflow portion of the valve. If there is an incomplete apposition, the outer skirt can conform to the anatomy, close the gaps, and reduce the risk of PVL. When calcifications are located on the edges of the annulus, PVL is common with the SAPIEN XT THV but dramatically reduced with the SAPIEN 3 THV. If the calcification extends from the annulus into the entire LVOT, there is always an incomplete apposition of the either valve frame; however, the resulting PVL is reduced by the outer skirt of the SAPIEN 3. In 165 consecutive SAPIEN 3 patients, 89.7% (n = 145) had none or a trace PVL and there were no patients with moderate or severe PVL. The new generation SAPIEN 3 valve allows more challenging anatomies to be treated, requires less oversizing, and can reduce PVL.

[Atrial fibrillation in Germany--epidemiology, diagnosis, treatment and costs]

Atrial fibrillation is the most common cardiac arrhythmia. It is an independent risk factor for cardiovascular complications and stroke. The treatment options for atrial fibrillation have changed significantly in recent years by new drugs and ablative procedures. It is based on the principal strategies of anticoagulation, rhythm and rate control. Goal is to reduce symptoms and subsequent events. Although the costs of about 700 to pound 800 per patient per year are rather high, new treatment options might be associated with a reduction in event rates and an increase in quality adjusted life years (QALYs). The aim of this review is to give a practical overview of the epidemiology, diagnosis, treatment and costs to pharmacists who have a key role in the implementation of pharmacotherapy of atrial fibrillation.

Diabetes prevalence and metabolic risk profile in an unselected population visiting pharmacies in Switzerland

Background

Diabetes represents one of the major health challenges in Switzerland, and early diagnosis and treatment is mandatory to prevent or delay diabetes-related morbidity and mortality. For the purpose of identifying affected individuals, early screening in pharmacies is a valuable option. In this survey, we aimed to determine blood glucose and metabolic control in an unselected population of individuals visiting Swiss pharmacies.

Methods

The subjects responded to a short questionnaire and underwent a single capillary blood glucose test for screening purposes. They were classified as normal, indeterminate, impaired fasting glucose, and diabetes according to predefined blood glucose levels.

Results

A total of 3135 individuals (mean age 56 years) in 18 cantons were screened in November 2010; of these, 4.2% (95% confidence interval [CI] 3.5–4.9) had previously been diagnosed with diabetes. Diabetes was newly diagnosed in 1.9% (95% CI 1.5–2.4), and 11.5% (95% CI 10.4–12.6) had impaired fasting glucose. Subjects with impaired glucose control had an increased body mass index, a frequent family history of diabetes, hypertension, hypercholesterolemia, smoking, and a low level of physical activity. Prevalence of impaired glucose control was different between the French/Italian-speaking part of Switzerland (new diabetes 4.9%; impaired fasting glucose 12.7%) and the German-speaking part (new diabetes 1.9%; impaired fasting glucose 10.3%).

Conclusion

Our study shows a 6.1% prevalence of diabetes, of which about a third (1.9%) was previously undiagnosed, and 11.5% had impaired fasting glucose. Therefore, screening initiatives in pharmacies may be suitable for detecting people with undiagnosed diabetes.

Microalbuminuria independently correlates to cardiovascular comorbidity burden in patients with hypertension

BACKGROUND

Microalbuminuria (MAU) is a marker for endothelial dysfunction and a predictor of cardiovascular events. Cardiovascular risk and mortality are mainly influenced by associated morbidities and risk factors.

METHODS AND RESULTS

The present analysis aimed to investigate the relationship between the number of cardiovascular comorbidities and both the prevalence of MAU and the extent of albuminuria (measured as urinary albumin excretion, UAE) in 21,867 high-risk hypertensive patients included in the I-SEARCH study. A total of 6,945 patients (32 %) suffered from at least one comorbidity, out of which 5,437 patients (25 %) had one cardiovascular comorbidity, 1,163 (5 %) patients had two, and 345 (2 %) had ≥3. The prevalence of MAU increased from 54 % in patients without cardiovascular comorbidity to 74 % in the presence of ≥3 comorbidities (p < 0.01). In a multivariate analysis, the presence of ≥3 cardiovascular comorbidities nearly doubled the risk for MAU (HR 1.79, CI 1.07-2.68, p = 0.025). Compared to other comorbidities, patients with left ventricular hypertrophy had the highest prevalence of MAU (68 %, p < 0.01). The extent of UAE was related to the number of concomitant disease and increased significantly in patients with ≥3 comorbidities compared to patients with no comorbidity (UAE of 80 mg/L: 12-22 %, p < 0.01; UAE of 150 mg/L: 8-19 %, p < 0.01).

CONCLUSIONS

In hypertensive patients at high cardiovascular risk, both the prevalence of MAU and the extent of albuminuria increase with the number of comorbidities.

Treatment of hypertension in the elderly: data from an international cohort of hypertensives treated by cardiologists

Hypertension in the elderly is a major risk factor for cardiovascular disease. We aimed to analyze determinants of blood pressure (BP) control across different age groups. Population of a large global survey on hypertension treatment and control including 18927 patients was analyzed. A logistic regression analysis was conducted to estimate BP control rates and the prevalence of antihypertensive drug usage according to age. Systolic BP control decreased from 29.6% (95% confidence intervals (CI) 26.0;33.5) at 18-40 years to 22.4% (20.8;24.2) at >75 years (P<0.0001), and diastolic BP control increased from 31.6% (27.9;35.6) to 57.3% (55.2;59.3), respectively (P<0.0001). BP control was worse in diabetic patients, but did not differ substantially with co-morbid conditions, except for a better control in patients with myocardial infarction (MI) (P<0.05). The use of ≥ 3 antihypertensive drugs increased with age from 16.1 to 37.8% (P<0.0001) due to a more frequent use of loop diuretics (P<0.0001), thiazides (P<0.0001), angiotensin-converting enzyme (ACE) inhibitors (P<0.0001) and calcium channel blockers (P<0.0001). About one third of patients received non-guideline-recommended drug-drug combinations. BP control is largely unsuccessful with increasing age. Owing to frequent inadequacies in the combination of antihypertensive drugs, future guidelines and educational programs should devote increased attention to the choice of optimal drug-drug combinations in the elderly.

Regional differences of glycaemic control in patients with type 2 diabetes mellitus in Switzerland: a national cross-sectional survey

AIMS

We investigated contemporary diabetes care, quality of glycaemic control, and progression of obesity in patients with diabetes mellitus in different cultural regions within Switzerland.

METHODS

Overall, 1121 patients treated for type 2 diabetes mellitus by 134 general practitioners were enrolled in this representative, national, cross-sectional survey and were followed retrospectively from the start of diabetes treatment. Patients were classified into four cultural regions; the German, French, Italian and Romansh speaking parts of Switzerland.

RESULTS

During 5.5 ± 5.1 years of diabetes treatment (retrospective survey), mean HbA1c decreased from 8.28 ± 2.01% to 7.03 ± 1.24%, fasting glucose decreased from 9.97 ± 3.86 to 7.52 ± 2.23 mmol/l, and BMI decreased from 30.2 ± 5.5 to 29.8 ± 5.6 kg/m² (p <0.001 for all parameters). Insulin therapy was associated with a larger improvement of mean HbA1c (-1.66 ± 2.33% vs. -1.15 ± 1.91%, p = 0.001) and an increase in BMI (+0.36 ± 2.92 vs. -0.63 ± 2.60 kg/m2, p <0.001). At the time when the cross-sectional survey was conducted, the mean HbA1c and fasting glucose were higher in the Italian part compared to other regions (7.72 ± 1.60% and 9.03 ± 2.49 mmol/l, respectively, p <0.001), and lower in the German part (6.89 ± 1.02% and 7.25 ± 2.02 mmol/l, respectively, p <0.001). In comparison to other regions, biguanides were more often used in the French part (86.1% versus 75.7%), insulin secretagogues in the Italian part (69.9% versus 37.8%), thiazolidinediones in the Romansh part (34.1% versus 17.8%), and insulin was more often used in the German part of Switzerland (27.0% versus 17.1%) (p <0.01 for all parameters).

CONCLUSIONS

Efforts to identify regional-cultural differences and attempts to overcome associated potential barriers should be emphasised in any health care system when aiming for better diabetic patient care.

Blood pressure management in a cohort of hypertensive patients in Germany treated by cardiologists

BACKGROUND

In Germany, an estimated 20-25 million patients suffer from hypertension. Blood pressure control rates are, however, lower than in many other European countries and the USA. The present analysis reports blood pressure treatment and control rates in Germany in patients with hypertension treated by cardiologists.

METHODS

The present analysis reports data from a German subgroup analysis of a large, multinational, observational survey i-SEARCH that recruited patients in 2005/2006. It reports blood pressure readings, drug utilization and control rates in cardiology practice.

RESULTS

A total of 4,982 patients were documented at 417 sites. Mean systolic/diastolic blood pressure (SBP/DBP) was 152 ± 19.5/88.4 ± 11.5 mmHg. SBP was 1.3 mmHg higher in men than in women (p = 0.021). The majority of patients had an SBP between 141 and 160 mmHg and 31.4% of patients had normal SBP. Overall blood pressure control rate was only 11.6% [95% CI 10.7-12.6] in treated patients. It was different in men [10.2%; 95% CI 9.0-11.6] than in women [8.1%; 95% CI 7.1-9.4; p = 0.008] and higher in patients without diabetes [12.7%; 95% CI 11.6-14.0] than in those with diabetes [4.3%; 95% CI 3.4-5.4; p < 0.0001]. One-third of patients received either monotherapy or dual therapy, or three and more drugs, respectively; 42.2% of patients received guideline-recommended dual combination therapy. A combination of beta-blockers + ACE inhibitors was most frequently prescribed (30.8%).

CONCLUSIONS

Our data indicate a low level of blood pressure control, especially in patients at an increased risk for cardiovascular events, such as those with diabetes or cardiovascular comorbidities. Major efforts are required to improve hypertension management as recommend by current treatment guidelines.

A global perspective on blood pressure treatment and control in a referred cohort of hypertensive patients

Hypertensive patients with cardiovascular (CV) comorbidities are at increased risk, and cardiologists' care should put particular emphasis on controlling blood pressure. Data on blood pressure treatment and control and drug utilization on a global scale, however, are scarce. Aiming to resolve this lack of information, the authors analyzed the data of International Survey Evaluating Microalbuminuria Routinely by Cardiologists in Patients With Hypertension (i-SEARCH) to gain further insights into national and regional blood pressure control and antihypertensive pharmacotherapy prescribed in cardiology practice. A total of 22,282 patients with hypertension from 26 countries were enrolled in 2005/2006. A total of 18,652 patients were treated (mean age, 63.0±11.4 years; 52.2% male; mean body mass index, 28.9 kg/m2). Mean systolic blood pressure was 148.2±19.8 mm Hg and diastolic blood pressure was 86.7±11.6 mm Hg. Blood pressure was controlled in 8.3% of diabetic and 25.3% of nondiabetic patients (21.2% overall), with particularly good control rates in North and Latin America (28.0% and 30.6%, respectively). A total of 31.2% of patients were treated with 1, 39.7% with 2, and 29.1% with ≥3 drugs. β-blockers were being used most frequently (47.9%), in both monotherapy and combination therapy despite low numbers of patients with respective compelling indications for their use. The present data illustrate the potential for an improvement of blood pressure treatment and control in daily cardiology practice.

Burden of diabetes in the adult Chinese population: A systematic literature review and future projections

BACKGROUND

The diabetes epidemic in China imposes an increasing burden on the health care system and the economy. We derived prospective diabetes prevalence rates in China until 2016 from a systematic review of the published literature in the period 1987-2007. The results could help to guide resources of the Chinese health care system in order to address the diabetes epidemic.

METHODS

We selected articles published in the English/Chinese languages from MEDLINE and the China Wanfang Digital Database using the keywords "China", "diabetes mellitus", "prevalence", and "epidemiology" in order to estimate the current diabetes prevalence in China. For projecting future prevalence rates, we considered the population growth, and assumed that China's diabetes prevalence in first tier cities in 2016 would equal Hong Kong's diabetes prevalence in 2007.

RESULTS

The number of Chinese adults with diabetes is projected to rise from 53.1 million in 2009 to 76.1 million in 2016. The estimated diabetes prevalence rate in China in 2009 was 3.9% (urban 5.2%, rural 2.9%) and is projected to increase to 5.4% (urban 6.9%, rural 3.8%) in 2016, corresponding to an annual consolidated aggregate growth rate of 4.6%.

CONCLUSION

We estimate a considerably higher diabetes prevalence in the adult Chinese population than that reported in previous studies. The diabetes prevalence will continue to rise in the future, which points to the importance of increasing awareness and better diagnosis of diabetes in China.

Smoking is associated with a high prevalence of microalbuminuria in hypertensive high-risk patients: data from I-SEARCH

BACKGROUND

Microalbuminuria (MAU) is a marker of endothelial dysfunction and a predictor of cardiovascular events. The effects of cigarette smoking on the prevalence of MAU in a high-risk population with arterial hypertension are unclear.

METHODS

The International Survey Evaluating Microalbuminuria Routinely by Cardiologists in patients with Hypertension (I-SEARCH) documented the clinical profile of 20,364 patients with arterial hypertension and cardiovascular risk factors. In this population, 13,690 patients had no history of smoking, 4,057 patients were former smokers and 2,617 patients were current smokers.

RESULTS

The prevalence of MAU was associated with the smoking status. Consumption of 1-20 cigarettes per day leads to an increase of 6.8% in the prevalence of MAU compared to non-smokers (P < 0.001). Smoking of >20 cigarettes per day was associated with a 12.5% higher prevalence of MAU compared to non-smokers, while former smokers had a 4.7% higher prevalence of MAU. Multivariable analysis revealed that smoking was independently associated with MAU [odds ratio (OR) smoking vs. non-smoking 1.16; 95% confidence interval (CI) 1.01-1.33; P < 0.05]. Particularly, a consumption of >20 cigarettes per day was associated with high odds for MAU (OR 1.33; CI 1.01-1.75; P < 0.05). Interestingly, independently of blood pressure, the use of an angiotensin receptor blocker and an ACE was associated with significantly reduced odds ratio for MAU in the smoking group, while there was no significant association in the non-smoking group.

CONCLUSION

The prevalence of MAU in hypertensive patients is higher in smokers than in non-smokers with a strong dose dependency.

Albuminuria: pathophysiology, epidemiology and clinical relevance of an emerging marker for cardiovascular disease

Albuminuria has emerged from being a sign of early kidney disease in diabetes to an independent predictor of cardiovascular risk. Epidemiological studies suggest that microalbuminuria (30-300 mg/d) is present in 5-19% of the general population, in up to 23% of patients with hypertension and in up to 40% of patients with diabetes. Recent data suggest an even higher prevalence in certain patient populations. As it is associated with a variety of important cardiovascular risk factors, including prediabetes, dyslipidemia and the metabolic syndrome, detection of albumin in the urine represents an important diagnostic window for systemic micro- or macrovascular damage. Various studies have demonstrated the predictive value of all levels of albuminuria for future cardiovascular events in patients with diabetes, hypertension or overt cardiovascular disease, as well as in the general population. Annual screening for microalbuminuria is now recommended by international diabetes guidelines for patients with diabetes, and may be appropriate for nondiabetics with risk factors for cardiovascular disease.

Antihypertensive drug therapy and blood pressure control in men and women: an international perspective

Cardiovascular death represents the single largest cause of mortality in women with 70% of deaths attributable to modifiable risk factors, such as hypertension. This analysis aims at evaluating, whether there are gender disparities in antihypertensive drug usage and blood pressure (BP) control. We included 18 017 patients with arterial hypertension from the International Survey Evaluating Microalbuminuria Routinely by Cardiologists in patients with Hypertension (I-SEARCH). The study was conducted between September 2005 and March 2006 in 26 countries, and data on patient demographics, cardiovascular disease and risk factors, BP, and cardiovascular drug treatment were collected. Mean systolic blood pressure (SBP) was 2.1 mm Hg higher in women (150.6+/-0.35 mm Hg, n=8357/18 017) than in men (148.5+/-0.35 mm Hg; P<0.0001, n=9526/18 017), whereas no difference in diastolic BP was seen (88.2+/-0.20 vs 88+/-0.20 mm Hg; P=0.198). Gender differences in SBP were more pronounced in diabetic as compared with non-diabetic patients (3.5 vs 1.7 mm Hg, n=4272 vs n=13 611; P<0.0001) and became evident at an age 55 years old. Overall BP-control rate was 33.6% in men and 30.6% in women (P<0.0001) and was lower in diabetic as compared with non-diabetic patients. In all, 30% of patients used one, 40% used two and 30% used > or = 3 drugs without gender differences. Response rates to different drug regimens appeared to be similar. However, women received more frequently thiazides and beta-blockers, and less frequently ACE-inhibitors as monotherapy. Major efforts are required to improve BP-management, especially in women.

Usefulness of elevations in serum choline and free F2)-isoprostane to predict 30-day cardiovascular outcomes in patients with acute coronary syndrome

Our objectives were to evaluate the prognostic value of several biomarkers in patients with acute coronary syndrome (ACS) through an evaluation of the 30-day clinical outcomes. Multiple biomarkers have emerged as potentially useful in risk stratification of ACS. Specifically, markers of vascular inflammation and oxidative stress might be helpful in the determination of clinical outcomes. We evaluated patients presenting with chest pain. ACS was defined by symptoms of cardiac ischemia plus electrocardiographic changes or positive troponin I. Levels of serum troponin I, high sensitivity C-reactive protein, serum choline, and free F(2)-isoprostane were obtained. Patients were followed up for 30 days (n = 108) with determination of nonfatal myocardial infarction, congestive heart failure, need for revascularization, and death. Of the 108 patients, 26 had a cardiac event. Free F(2)-isoprostane and choline levels (but not high-sensitivity C-reactive protein levels) predicted 30-day cardiac events. To determine the value of choline and F(2)-isoprostane levels in predicting 30-day cardiac events, receiver operating curves were generated. The optimal cutoff point of these markers was a serum F(2)-isoprostane level of 124.5 pg/ml (r = 0.82) and a serum choline level of 30.5 mumol/L (r = 0.76). F(2)-isoprostane and choline had a positive predictive value of 57% and 44% and a negative predictive value of 90% and 89%, respectively. In conclusion, serum choline and free F(2)-isoprostane are predictors of cardiac events in ACS. A model that includes an array of biomarkers, including troponin, choline, and free F(2)-isoprostane, might be useful in predicting patients at greater risk of future events in ACS.

Prevalence of microalbuminuria and its associated cardiovascular risk: German and Swiss results of the recent global i-SEARCH survey

QUESTION UNDER STUDY

The aim of this study was to determine the prevalence of microalbuminuria (MAU) in hypertensive patients attending an office or hospital based cardiologist or internist. An additional aim was to describe associations between MAU and cardiovascular risk factors as well as to investigate the role of pharmacotherapy.

METHODS

International, observational, cross-sectional study of 22282 patients with 5605 attendees in Germany and Switzerland at 444 cardiology centers. Inclusion criteria were male and female outpatients, aged > or =18 years with currently treated or newly diagnosed hypertension (> or =140/90 mm Hg at rest on the day of the study visit) and no reasons for false positive dip stick tests. The main outcome measures were the prevalence of MAU, co-morbid cardiovascular risk factors or disease and their association with the presence of MAU, and the role of pharmacotherapy in modulating prevalence of MAU.

RESULTS

Prevalence of MAU in Germany and Switzerland (53.1%) was high, but lower when compared to the prevalence in "other countries" (OC, 60.2%). Routine MAU measurement was performed in 52.9% of the practices only (32.9% OC), although physicians regarded MAU to be important for risk assessment and therapeutic decisions. MAU is highly correlated with a wide variety of cardiovascular risk factors and co-morbid cardiovascular conditions including high waist circumference (55.1% [95%CI 56.0; 59.7]), diabetes (59.1% [56.8; 61.3]), atrial fibrillation (62.3% [57.4; 66.9]) and peripheral arterial disease (67.1% [61.6; 72.2]). Angiotensin receptor blockers (ARBs) appeared to be associated with the lowest risk of MAU (52.1%). Calcium channel blockers (CCBs) were used more frequent in patients with MAU (28.7%) than without (23.4%).

CONCLUSIONS

Patients with MAU are common in clinical cardiology and its presence is associated with a wide variety of cardiovascular risk factors and co-morbid cardiovascular conditions. A more aggressive multi-factorial treatment might help to reduce this risk constellation.

Abdominal obesity is associated with microalbuminuria and an elevated cardiovascular risk profile in patients with hypertension

Background

Overweight and obesity are frequently associated with preventable death and have emerged as a major challenge to public health. There is an ongoing debate on the role of abdominal obesity and its value in predicting cardiovascular and renal outcomes. The present analysis evaluates the prevalence of microalbuminuria (MAU) and conventional cardiovascular risk factors in relation to measures of general and abdominal obesity.

Methods

In this multinational, observational study, 20828 hypertensive out-patients from 26 countries including Europe, North and Latin America, Middle East, and Asia were analyzed. Urinary dipstick screening for MAU was performed as well as data on patient demographics, anthropometric measures, cardiovascular risk factors, comorbid conditions, and cardiovascular drug therapy collected. MAU prevalence was determined by a stepwise logistic regression analysis with cardiovascular risk factors as univariate.

Results

In the univariate analysis, MAU prevalence systematically increased with body mass index (BMI) from 54.4% (1st tertial) to 62.1% (3rd tertial) (p < 0.0001), an increase which was also observed for waist circumference (WC). At any level of BMI, MAU increased with WC from 53.5%, 54.8%, and 55.0% (1st tertial of WC in all three BMI tertials) to 61.4%, 62.1%, and 64.0% (3rd tertial of WC in all BMI tertials) (p < 0.0001). In the multivariate analysis, WC, but not BMI was independently associated with MAU. Furthermore, overweight/obesity were associated with the presence of modifiable and nonmodifiable risk factors.

Conclusion

An abnormal WC, but not BMI appears to be independently associated with MAU, an early marker of cardiovascular and renal risk. Increasing WC confers an incremental risk for MAU at any level of BMI, underlining the prognostic importance of abdominal fat accumulation beyond general obesity.

Atrial fibrillation and heart rate independently correlate to microalbuminuria in hypertensive patients

AIMS

To investigate the relationship between microalbuminuria (MAU) and atrial fibrillation (AF) and to further evaluate whether the heart rate dependency of MAU in patients without AF is maintained in patients with a history of AF.

METHODS AND RESULTS

The International Survey Evaluating Microalbuminuria Routinely by Cardiologists in patients with Hypertension (I-SEARCH) included 18,900 patients without and 1705 patients with a history of AF suffering from hypertension and other risk factors for cardiovascular disease in 26 countries worldwide from September 2005 to March 2006. Heart rate, blood pressure, urinary albumin excretion, and an estimated glomerular filtration rate were determined among other parameters. The prevalence of MAU was higher at higher heart rate in both patients with and without a history of AF. Prevalence of MAU was about 10% higher in patients with a history of AF (P < 0.001). Male gender, the presence of diabetes mellitus, a higher heart rate, and a higher diastolic blood pressure were independently associated with increased odds for MAU in patients without and with a history of AF.

CONCLUSION

The prevalence of MAU in hypertensive patients with cardiovascular risk factors is related to heart rate and significantly higher in patients with a history of AF.

Prevalence of albuminuria and cardiovascular risk profile in a referred cohort of patients with type 2 diabetes: an Asian perspective

BACKGROUND

Microalbuminuria (MA) is a risk marker for diabetic nephropathy and cardiovascular (CV) disease (CVD) in patients with diabetes. This study aimed to describe the prevalence of albuminuria, CV risk factors, and treatments for renal and CV protection in an Asian population with type 2 diabetes.

METHODS

This cross-sectional study conducted in eight Asian countries enrolled normotensive/hypertensive adults with type 2 diabetes without known proteinuria and/or non-diabetic kidney disease. Exclusion criteria were type 1 diabetes, menstruation, pregnancy, and acute fever. A single random urinary albumin/creatinine test was carried out in all patients.

RESULTS

Of 8,561 patients, 14% had diabetic retinopathy, and 17% and 21% had history of CV disease and smoking, respectively. Normoalbuminuria was seen in 44%, MA in 44%, and macroalbuminuria in 12%. Target glycosylated hemoglobin (HbA1c) (<7%) was reached in only 37% of 3,834 patients with available values. Diabetes was managed by diet alone in 6%, while others received oral hypoglycemic drugs and/or insulin. In total, 75% did not reach target blood pressure (BP) of <or=130/80 mm Hg. Antihypertensive drugs were prescribed to 52%, with the number of drugs increasing as the level of systolic BP increased. Drugs blocking the renin-angiotensin system were most commonly prescribed, followed by calcium channel blockers. Lipid-lowering drugs and anticoagulant/antiplatelet agents were used in about 30% and 25% of patients, respectively.

CONCLUSIONS

Asian patients with type 2 diabetes had a high prevalence of MA and reduced kidney function. Furthermore, BP and HbA1c control was only achieved in a minority of patients. Aggressive risk management by administration of reno- and cardioprotective treatments is urgently needed.

Association of heart rate with microalbuminuria in cardiovascular risk patients: data from I-SEARCH

BACKGROUND

Microalbuminuria (MAU) is an indicator of impaired renal function and a relevant risk predictor for cardiovascular events. An increased heart rate is closely correlated with increased cardiovascular mortality. The International Survey Evaluating Microalbuminuria Routinely by Cardiologists in Patients with Hypertension (I-SEARCH) investigated 21 050 patients with hypertension and risk factors for cardiovascular disease. In patients in sinus rhythm (n = 18 900) the relationship between increased heart rate and the prevalence of MAU was analysed.

METHODS AND RESULTS

The study was performed in 26 countries worldwide from September 2005 to March 2006. Heart rate, blood pressure, urine albumin and serum creatinine were measured as key parameters. With increasing heart rate (> 80 bpm to < 120 bpm) the proportion of patients with MAU increased from 63 to 69% (P < 0.0001). The odds ratio (OR) for MAU increased with increasing heart rate [heart rate 80-100 bpm compared with 60 bpm: OR, 1.47; 95% confidence interval (CI), 1.29-1.68; P < 0.0001; and heart rate 100-120 bpm compared with 60 bpm: OR, 1.56; 95% CI, 1.22-1.99; P = 0.0004]. The prevalence of MAU was similar whether or not patients were receiving beta-blockers; but MAU was significantly reduced in physically active patients compared with sedentary patients (OR, 0.78; 95% CI, 0.73-0.84; P < 0.0001).

SUMMARY

These results show that heart rate is an independent predictor for the prevalence of MAU in hypertensive patients with cardiovascular risk factors. In contrast to beta-blocker therapy, physical activity markedly decreased MAU with increasing heart rates. Further controlled and prospective studies are needed to show that lowered heart rates in combination with MAU can significantly reduce kidney damage, as well as cardiovascular events.

[Prevention of cardiovascular disease by blocking the endocannabinoid system]

Risk factors for the development of cardiovascular disease, in particular myocardial infarction, are smoking, high body weight, sedentary lifestyle, unfavorable diet, high blood pressure, elevated fasting glucose or diabetes, and dyslipidemia (Tables 1 and 2). If the risk for cardiovascular mortality of 5% (using the SCORE Score) or for nonfatal cardiovascular events of 20% (PROCAM Score) within the next 10 years is exceeded or overt atherosclerosis or type 2 diabetes mellitus is present, the use of (poly)pharmacotherapy is indicated and lifestyle intervention (diet, physical activity) alone is not sufficient at that point (Figure 1). A new therapeutic option, able to modify a number of cardiovascular risk factors at a time, is the blockade of the so-called endocannabinoid system (Figure 2). For rimonabant not only a reduction of body weight and waist circumference was shown in clinical trials, its use was also accompanied by an increase of HDL cholesterol, a decrease in triglycerides, and a reduction in HbA1c and fasting blood glucose (Table 4). Together with preliminary data on the efficacy in smoking cessation, rimonabant has a therapeutic impact on four out of eight relevant risk factors in order to prevent myocardial infarction as promoted by the American College of Cardiology/American Heart Association. Currently, a large clinical study program is ongoing to further investigate the role of rimonabant in managing cardiovascular risk (Table 3). Published clinical trial results have revealed, that rimonabant is generally well tolerated (most frequent side effect: nausea) and the data are promising with regard to the potential future role of rimonabant in managing cardiovascular risk.

BP goal achievement in patients with uncontrolled hypertension : results of the treat-to-target post-marketing survey with irbesartan

BACKGROUND AND OBJECTIVE

Despite the fact that high BP is a leading risk factor for cardiovascular morbidity and mortality, BP goals are achieved in less than 10-30% of hypertensive patients. Irbesartan alone or in combination with hydrochlorothiazide has been shown to control BP in >70% of hypertensive patients in clinical trials. We set out to investigate the role in clinical practice of irbesartan in improving BP in uncontrolled hypertensive patients with a particular focus on patients with the metabolic syndrome through analysis of data from a post-marketing surveillance study.

METHODS

A multicentre, prospective, post-marketing surveillance study was conducted over 9 months in 14 200 patients aged > or =18 years with previously uncontrolled hypertension (either receiving therapy or newly diagnosed), paying particular attention to a subgroup of patients receiving irbesartan/hydrochlorothiazide as first-line combination therapy. BP was measured by a sphygmomanometer. The main outcome measures were systolic BP (SBP) and diastolic BP (DBP) reduction, response rate (DBP reduction of > or =10mm Hg or to <90 mm Hg), and BP normalisation (SBP <140 and DBP <90 mm Hg) in patients treated with irbesartan alone or in combination with hydrochlorothiazide. Analyses per patient subgroup, previous medication and whether treatment was initiated by the treating physician as first-line combination therapy were conducted. The number and nature of adverse events were documented.

RESULTS

Use of irbesartan 300 mg/day as monotherapy in previously uncontrolled patients resulted in a significant reduction in SBP/DBP (-26.8/-13.3mm Hg, p < 0.0001), which was comparable to the subgroup of patients with the metabolic syndrome (-26.3/-13.0mm Hg, p < 0.0001 vs baseline). Combination therapy (irbesartan 300 mg/hydrochlorothiazide 12.5mg once daily) lowered BP by -27.9/-14.2mm Hg (p < 0.0001) in previously uncontrolled patients; again the subgroup of patients with the metabolic syndrome achieved a comparable BP reduction (-27.5/-14.1mm Hg, p < 0.0001 vs baseline). Overall, no linear dose-response relationship was observed. Use of irbesartan/hydrochlorothiazide as first-line combination therapy was effective (BP normalisation rates between 65.7% and 78.6%) and safe. The mean number of antihypertensive tablets taken was reduced and after a mean period of 9 months, 92% of patients were still taking irbesartan therapy.

CONCLUSION

The study demonstrates that treatment with an irbesartan-based regimen for 9 months results in a strong BP reduction and is feasible as first-line combination therapy. Similar BP reductions were observed in the subgroup of patients with the metabolic syndrome. Compliance with treatment is particularly good, with >90% of patients continuing with treatment after 9 months.

Cardiovascular risk in obese hypertensive patients taking various antihypertensive drugs

OBJECTIVE

Obese patients often present with multiple co-morbid conditions, including hypertension, which are associated with an increased cardiovascular (CV) risk. We aimed to assess the risk factor profiles of primary-care patients with obesity and hypertension in order to estimate their fatal CV risk in total and according to use of various antihypertensive drugs.

METHODS

This was a post-hoc analysis of data from a recent observational study involving 72 479 hypertensive patients in 6989 general practices across Germany. Almost all patients (92.3%) were overweight or obese. The 10-year risk for fatal CV events was determined using the SCORE algorithm as published by the European Society of Cardiology.

RESULTS

Overall, 68% of patients had one or more diseases or conditions in addition to obesity and hypertension. The 10-year fatal CV risk was lowest in the youngest normal weight group (1.7%), and highest in the oldest obese group (26%). Men had a higher risk than women, and risk rose with increasing age. The risk factor profile appeared to differ between patients treated with various antihypertensive classes, e.g. angiotensin II type 1 receptor antagonists were associated with lower risk, diuretics with higher risk. There were moderate differences within drug classes.

CONCLUSIONS

According to this cross-sectional data, fatal CV risk is strongly increased in obese patients, especially in men and in older age groups. While there were strong associations between use of certain drugs and metabolic risk markers and overall fatal CV risk, the causality of these associations remains to be determined.

The effects of extended-release niacin on carotid intimal media thickness, endothelial function and inflammatory markers in patients with the metabolic syndrome

BACKGROUND

Niacin is an agent that significantly increases high-density lipoprotein cholesterol (HDL-C), but its effects on surrogate markers of atherosclerosis and inflammatory markers are less clear. We studied the effects of niacin on carotid intimal media thickness (IMT), brachial artery reactivity as well as markers of inflammation and the metabolic profile of patients with metabolic syndrome.

METHODS AND RESULTS

Fifty patients with the metabolic syndrome (Adult Treatment Panel (ATP) III criteria) were randomised to either extended-release niacin (1000 mg/day) or placebo. After 52 weeks of treatment, there was a change of carotid IMT of +0.009 +/- 0.003 mm in the placebo group and -0.005 +/- 0.002 mm in the niacin group (p = 0.021 between groups). Endothelial function improved by 22% in the group treated with niacin (p < 0.001), whereas no significant changes were seen in the placebo group. High sensitivity C-reactive protein decreased by 20% in the group treated with niacin for 52 weeks (p = 0.013). Niacin increased HDL-C (p < 0.001) and decreased low-density lipoprotein cholesterol and triglycerides (p < 0.001) significantly, and there were no adverse effects on fasting glucose levels after 52 weeks of treatment.

CONCLUSION

Extended-release niacin therapy effects a regression in carotid intimal medial thickness and improvement in metabolic parameters (increased HDL and reduced triglycerides). Furthermore, extended-release niacin may demonstrate an anti-atherogenic effect in the metabolic syndrome by improving endothelial function and decreasing vascular inflammation.

[Long-term follow-up of cardiovascular risk markers in patients with hypertension. Rationale, design, and baseline characteristics of the i-Search Plus Registry]

BACKGROUND

Cardiovascular risk markers like microalbuminuria (MAU), highly sensitive C-reactive protein (hsCRP) and brain natriuretic peptide (BNP) currently gain importance to estimate risk in trials and clinical practice. Blockade of the renin-angiotensin system (RAS) has been shown to reduce some of these risk markers in clinical trials, but validation of their time course and role in clinical practice is still pending.

DESIGN

To fill this gap, the design of a nationwide registry study was chosen in which patients attending their cardiologist were observed for 12 months and the effect of blocking the RAS with the angiotensin II receptor blocker irbesartan was documented. Primary question: risk for mortality and the incidence of cardiovascular events in relation to baseline values of MAU, hsCRP, and BNP. Secondary questions: correlations between cardiovascular risk markers (1) amongst each other with respect to cardiovascular events, (2) with clinical findings (echocardiography, electrocardiogram), (3) with the heart rate, (4) with further metabolic parameters (blood sugar, HbA(1c), etc.), and (5) with blood pressure control.

RESULTS

Until April 1, 2006, 2,149 patients were recruited in 305 centers in Germany. Patients had a mean age of 61.4 (+/- 11.3) years. Waist circumference was 103.6 (+/- 13.5) cm. 95.1% of all patients had arterial hypertension at inclusion (> or = 140/90 mmHg). The mean value for albumin/creatinine was 68.9 (+/- 307.5) mg/g (n = 2,100), for hsCRP 4.6 (+/- 8.3) mg/l (n = 2,136), and for proBNP 236.5 (+/- 557.3) pg/ml (n = 2,138).

CONCLUSION

The present register will elucidate the time course and the interdependence of the cardiovascular risk markers MAU, hsCRP and proBNP as well as their prediction of cardiovascular endpoints in hypertensive individuals. In addition, the role of RAS-blocking agents will be evaluated. A valuable contribution to estimate risk and to optimize care for cardiovascular high-risk patients in clinical practice can be expected.

Irbesartan for the treatment of hypertension in patients with the metabolic syndrome: a sub analysis of the Treat to Target post authorization survey. Prospective observational, two armed study in 14,200 patients

Objectives

The metabolic syndrome is a cluster of cardiovascular risk factors leading to an increased risk for the subsequent development of diabetes and cardiovascular morbidity and mortality. Blocking the renin-angiotensin system has been shown to prevent cardiovascular disease and delay the onset of diabetes. Irbesartan is an angiotensin receptor blocker (ARB) which has been shown to possess peroxisome proliferator-activated receptor gamma (PPARγ) activating properties, and to have a favorable metabolic profile. Current discussion is whether the addition of small doses of hydrochlorothiazide changes this profile. Therefore the efficacy, safety and metabolic profile of Irbesartan either as monotherapy or in combination therapy was assessed in patients with the metabolic syndrome in a large observational cohort in primary care.

Research design and methods

Multicenter, prospective, two-armed, post authorization study over 9 months in 14,200 patients with uncontrolled hypertension with and without the metabolic syndrome (doctors' diagnosis based on the Adult Treatment Panel III criteria 2001). Blood pressure was measured sphygmomanometrically and cardiovascular risk factors making up the criteria for the metabolic syndrome were assessed.

Main outcome measures

Systolic (SBP) and diastolic (DBP) blood pressure reduction, – response, and – normalization (systolic and diastolic), changes in fasting glucose, waist circumference (abdominal obesity), serum triglycerides and HDL cholesterol as well as the proportion of patients fulfilling the criteria for the metabolic syndrome. Number and nature of adverse events (AEs).

Results

After 9 month the use of Irbesartan in monotherapy resulted in a significant reduction of blood pressure (SBP: -26.3 ± 10.1 mmHg/DBP-13.0 ± 6.6 mmHg, both p < 0.0001) in patients with the metabolic syndrome. This was accompanied by a reduction in cardiovascular risk factors: HDL cholesterol (+3.6 ± 7.2 mg/dl in men, +3.8 ± 6.5 mg/dl in women, both p < 0.0001), serum triglycerides (-28.6 ± 52.1 mg/dl, p < 0.0001), fasting blood glucose (-8.4 ± 25.1 mg/dl, p < 0.0001) and waist circumference (-2.4 ± 11.9 cm in men, -1.2 ± 14.2 in women, both p < 0.0001) were significantly improved. Irbesartan combination therapy (12.5 mg HCTZ) in patients with the metabolic syndrome: blood pressure reduction (SBP: -27.5 ± 10.1 mmHg/DBP: -14.1 ± 6.6 mmHg, both p < 0.0001), improvement in HDL cholesterol (+4.0 ± 6.8 mg/dl in men, +3.4 ± 6.8 in women, both p < 0.0001), triglycerides (-34.1 ± 52.6 mg/dl, p < 0.0001), fasting blood glucose (-10.0 ± 24.7, p < 0.0001) and waist circumference (-3.2 ± 12.7 cm in men, -1.7 ± 14.4 in women, both p < 0.0001). Tolerability was excellent: only 0.6% of patients experienced an AE.

Conclusion

There was a significant improvement in blood pressure and metabolic risk factors as a result of Irbesartan treatment. There was no evidence of a difference between monotherapy and combination therapy with regard to the cardiovascular risk profile.

Potential role of statin therapy in heart failure, atrial fibrillation and aortic stenosis

3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, or statins, are widely prescribed throughout the world, and considerable evidence has indicated their powerful effects in ischemic forms of cardiovascular disease. Recently, several trials have demonstrated that statins have pleiotropic effects beyond their lipid-lowering capacities. These findings may play a role in the use of statins to manage forms of cardiovascular disease that may or may not have an ischemic etiology: congestive heart failure, atrial fibrillation and aortic stenosis.

Atorvastatin: beyond lipid-lowering effects in the diabetic population

Statins are the mainstay of therapy in coronary artery disease and hypercholesterolemia. Atorvastatin is a 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor that is taken once daily. It has been shown to considerably reduce cardiovascular mortality events. Recently, several trials have demonstrated that atorvastatin has pleiotropic effects beyond its lipid-lowering capacities. Atorvastatin is especially beneficial in diabetics for stroke prevention and improving cardiovascular mortality risk.

Endotoxin induces desensitization of cardiac endothelin-1 receptor signaling by increased expression of RGS4 and RGS16

OBJECTIVE

Endotoxin (LPS)-induced acute cardiac failure during sepsis is associated with alterations in G protein mediated signal transduction. We therefore examined the expression of the G proteins G(i), G(q), and G(s) and of four 'regulators of G protein signaling' (RGS) proteins, RGS1, RGS4, RGS5, and RGS16 in rat hearts.

METHODS

For in vivo experiments, Wistar rats were treated with 600 microg/day E. coli LPS, intravenously) and hearts were excised after 6, 24 and 72 h. Cultured neonatal rat cardiomyocytes were treated with 4 microg/ml LPS for 24 and 72 h. Isolated membrane proteins were used for Western blot analysis and for evaluation of phospholipase C (PLC) activity. RGS16 mRNA was detected by RNAse protection.

RESULTS

LPS induced G(i) protein 1.4-fold 72 h after in vivo administration of LPS, whereas expression of G(s) and G(q) was unaltered. After 6 h of LPS treatment, RGS16 mRNA was transiently up-regulated 3.7-fold, followed by transient protein induction (24 h: 2.5-fold; 72 h: 1.5-fold). Similarly, RGS4 protein was transiently induced (24 h: 3.1-fold; 72 h: 1.5-fold), whereas expression of RGS1 and RGS5 was not altered. Similar to the LPS-treated rat hearts, RGS16 expression was transiently induced by LPS in cultured neonatal rat cardiomyocytes (24 h: 1.6-fold, 72 h: 0.9-fold). To determine the functional consequences of the RGS protein induction phospholipase C (PLC) activity was analyzed in membranes obtained from solvent and LPS-treated hearts. Basal and endothelin-1-stimulated PLC activity was transiently repressed by LPS with a maximum after 24 h although no apparent changes in PLCbeta1 or endothelin receptor expression could be detected.

CONCLUSION

These data suggest that the rapid up-regulation of cardiac RGS4 and RGS16 is associated with a desensitization of endothelin-1 receptor signaling. Up-regulation of these RGS proteins may thus be involved in the early onset of cardiac failure during sepsis.

Endotoxin and cytokines alter contractile protein expression in cardiac myocytes in vivo

Release of bacterial endotoxin and cytokines induce cardiac failure during sepsis. We investigated the direct effects of E. coli endotoxin (lipopolysaccharide, LPS) and cytokines induced by LPS on the cardiac myocyte gene program. For in vivo-experiments adult Wistar rats were given 600 microg/day LPS i.v. for 24 h or 7 days. In addition, cultured adult rat cardiac myocytes were treated with LPS, interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNFalpha), interferon-gamma (IFNgamma) or IL-6 for 24 h. mRNA expression was evaluated for cardiac-alpha-actin (cAct), skeletal-alpha-actin (skAct), beta- and alpha-myosin heavy chain (MHC). LPS induced betaMHC-mRNA 3.6-fold and repressed alphaMHC 2.7-fold and cAct 2.5-fold after 24 h in vivo. Up-regulation of betaMHC (3-fold) and repression of cAct (2.5-fold) were still observed after 7 days LPS infusion, whereas alphaMHC-mRNA levels had returned to normal. At the protein level, increased expression of betaMHC by LPS treatment occurred already after 24 h and was maintained thereafter. LPS had no influence on skAct-mRNA. Similar changes in contractile protein mRNA expression were observed in LPS-treated cardiomyocytes in culture, whereas the tested cytokines either activated (IL-1beta, IFNgamma) or repressed (TNFalpha, IL-6) both MHC-isoforms and cAct. In conclusion, LPS and proinflammatory cytokines induce changes in contractile protein expression that may contribute to the acute heart failure observed during endotoxaemia.

Dissociation of the effects of forskolin and dibutyryl cAMP on force of contraction and phospholamban phosphorylation in human heart failure

Forskolin and dibutyryl cyclic adenosine monophosphate (cAMP) stimulate force of contraction independent of beta-adrenoceptor stimulation. We studied their effects on force of contraction and phosphorylation of regulatory proteins in isolated electrically driven trabeculae carneae from failing human ventricles. The phosphorylation state of the regulatory protein phospholamban was studied because its phosphorylation usually faithfully follows contractility. For comparison, the phosphorylation state of the inhibitory subunit of troponin was studied. The phosphorylation state was inferred from in vitro phosphorylation of homogenates with cAMP-dependent protein kinase in the presence of radioactive gamma[32P]ATP Proteins were separated by electrophoresis, and radioactivity in the proteins of interest was quantified. The maximal positive inotropic effects occurred at 30 microM forskolin and were attenuated in comparison with the maximal effects to dibutyryl cAMP (1 mM). Both forskolin and dibutyryl cAMP enhanced phospholamban phosphorylation. However, phospholamban phosphorylation in intact trabeculae treated with 30 microM forskolin and 1 mM dibutyryl cAMP was comparable. It is suggested that phospholamban phosphorylation can be dissociated from inotropy at least in isolated trabeculae from failing human hearts.

Biological and prognostic significance of stratified epithelial cytokeratins in infiltrating ductal breast carcinomas

The biological significance of the differential expression of cytokeratin (CK) polypeptides in breast carcinomas is unclear. We examined the CK profiles of 101 primary infiltrating ductal breast carcinomas using monoclonal antibodies directed against 11 different CKs and against vimentin. Two major CK phenotypes were distinguished: first, a phenotype expressing only the simple-epithelial CKs 7 (variably), 8, 18 and 19, and secondly, a bimodal phenotype co-expressing significant amounts of one or more of the stratified-epithelial CKs 4, 14 and 17. The vast majority of G1 and G2 carcinomas had the simple-epithelium phenotype, as did a subgroup of G3 carcinomas. Interestingly, the majority (62%) of G3 carcinomas exhibited the bimodal phenotype, with the expression of CKs 4, 14 and 17 being statistically correlated with poor histological differentiation and absence of steroid hormone receptors. The distribution of vimentin only partially overlapped with that of these stratified-epithelial CKs. Prognostic analyses suggested that the presence of CKs 4, 14 and/or 17 was associated with short overall and disease-free survival in subgroups comprising G3, oestrogen-receptor-negative and vimentin-negative tumours. In node-positive tumours the correlation between these CKs and a shorter disease-free interval attained statistical significance (log rank, 0.0096). Thus, abnormal CK profiles in ductal breast carcinomas appear to reflect disturbed regulation of differentiation-related gene expression programmes and may prove to be of clinical value.

Hydralazine prevents nitroglycerin tolerance by inhibiting activation of a membrane-bound NADH oxidase. A new action for an old drug

Hydralazine has been shown to reduce mortality in patients with congestive heart failure when given concomitantly with isosorbide dinitrate. Recently, we demonstrated that nitrate tolerance is in part due to enhanced vascular superoxide .O2- production. We sought to determine mechanisms whereby hydralazine may prevent tolerance. Rabbits either received no treatment, nitroglycerin patches (1.5 micrograms/kg/min x 3 d), hydralazine alone (10 mg/kg/d in drinking water), or hydralazine and nitroglycerin. Aortic segments were studied in organ chambers and relative rates of vascular .O2- production were determined using lucigenin-enhanced chemiluminescence. Nitroglycerin treatment markedly inhibited relaxations to nitroglycerin (maximum relaxations in untreated: 92 +/- 1 vs. 64 +/- 3% in nitroglycerin-treated patients and increased vascular .O2- production by over two-fold (P < 0.05). Treatment with hydralazine in rabbits not receiving nitroglycerin significantly decreased .O2- production in intact rabbit aorta and increased sensitivity to nitroglycerin. When given concomitantly with nitroglycerin, hydralazine completely prevented the development of nitrate tolerance and normalized endogenous rates of vascular .O2- production. Studies of vessel homogenates demonstrated that the major source of .O2- was an NADH-dependent membrane-associated oxidase displaying activities of 67 +/- 12 vs. 28 +/- 2 nmol .O2-.min-1.mg protein-1 in nitroglycerin-treated vs. untreated aortic homogenates. In additional studies, we found that acute addition of hydralazine (10 microM) to nitroglycerin-tolerant vessels immediately inhibited .O2- production and NADH oxidase activity in vascular homogenates. The chemiluminescence signal was inhibited by a recombinant heparin-binding superoxide dismutase (HBSOD) demonstrating the specificity of this assay for .O2-. These observations suggest that a specific membrane-associated oxidase is activated by chronic nitroglycerin treatment, and the activity of this oxidase is inhibited by hydralazine, providing a mechanism whereby hydralazine may prevent tolerance. The ability of hydralazine to inhibit vascular .O2- anion production represents a novel mechanism of action for this drug.

Endotoxin and cytokines induce direct cardiodepressive effects in mammalian cardiomyocytes via induction of nitric oxide synthase

In patients with septic shock or inflammatory cardiac diseases like myocarditis myocardial contractility is depressed. These patients have elevated circulating levels of bacterial endotoxins (lipopolysaccharides, LPS) and pro-inflammatory cytokines like interleukin-1 beta (IL-alpha 1 beta) or tumor necrosis factor-alpha (TNF-alpha). It is not clear, whether LPS and/or cytokines have direct inotropic effects on cardiomyocytes and whether these effects are mediated via the L-arginine-nitric oxide synthase (NOS) pathway as demonstrated in vascular smooth muscle cells. Therefore, we examined the direct effects of LPS. IL-1 beta and TNF-alpha on contractility and cGMP content in isolated guinea-pig ventricular cardiomyocytes. Furthermore, the influence of the NOS inhibitor NG-nitro-L-arginine (L-NNA) and dexamethasone on these effects was studied as well as inducible NOS (iNOS) protein expression. LPS (1000 ng/ml), IL-1 beta (25 ng/ml) and TNF-alpha (100 ng/ml) decreased contractility by 48%, 55% and 65% and augmented cGMP content by 135%, 88% or 70% after long-term treatment (18 h) in cardiomyocytes, without altering contractility or cGMP content after short-term treatment (30 min). These effects were blocked by L-NNA (100 microM) and dexamethasone (3 microM). Furthermore iNOS protein was expressed in LPS- and cytokine-treated cardiomyocytes. These findings demonstrate that LPS. IL-1 beta and TNF-alpha have direct negative inotropic effects on cardiomyocytes, which are accompanied by an increase in cGMP content. These effects are mediated via de novo synthesis of a myocardial iNOS. The direct negative inotropic effects of endotoxins and cytokines on cardiomyocytes may in part contribute to the contractile dysfunction observed in patients with septic shock or inflammatory cardiac diseases.

Expression of inducible nitric oxide synthase in failing and non-failing human heart

Recently, a significant activity of inducible nitric oxide synthase (iNOS) has been reported in biopsies from failing hearts due to idiopathic dilated cardiomyopathy (IDC). Thus, a potential pathophysiological role of iNOS in IDC has been stated. In order to investigate, whether iNOS expression is of pathophysiological relevance in human heart failure, we measured iNOS protein expression and cGMP content in left ventricular myocardium from non-failing and failing human hearts. Immunoblot analysis revealed iNOS protein expression in four out of six failing hearts from septic patients, whereas no iNOS-protein expression was detected in either non-failing human hearts (n = 6) or failing hearts due to IDC (n = 9), ischemic heart disease (IHD, n = 7), Becker muscular dystrophy (BMD, n = 2) and mitoxantrone-induced toxic cardiomyopathy TCM, n = 1). cGMP content was increased by 130% in septic hearts, whereas there was no cGMP increase in hearts with IDC. IHD and BMD compared to non-failing hearts. We conclude, that the induction of iNOS may play a role in contractile dysfunction observed in septic shock, but is unlikely to be of major pathophysiological importance in end-stage heart failure due to IDC, IHD, BMD and TCM.