Early outcomes of out-of-hospital cardiac arrest after early defibrillation: a 24 months retrospective analysis.

INTRODUCTION: Cardiovascular disease remains the most common cause of death in the United States and most other Western nations. Among these deaths, sudden, out-of-hospital cardiac arrest claims approximately 1000 lives each day in the United States alone. Most of these cardiac arrests are due to ventricular fibrillation. Though highly reversible with the rapid application of a defibrillator, ventricular fibrillation is otherwise fatal within minutes, even when cardiopulmonary resuscitation is provided immediately. The overall survival rate in the United States is estimated to be less than 5 percent. Recent developments in automated-external-defibrillator technology have provided a means of increasing the rate of prompt defibrillation after out-of-hospital cardiac arrest. After minimal training, nonmedical personnel (e.g., flight attendants and casino workers) are also able to use defibrillators in the workplace, with lifesaving effects. Nonetheless, such programs have involved designated personnel whose job description includes assisting persons who have had sudden cardiac arrest. Data are still lacking on the success of programs in which automated external defibrillators have been installed in public places to be used by persons who have no specific training or duty to act. MATERIALS AND METHODS: All patients who had an out-of-hospital cardiac arrest between January 2003 and December 2004 and who received early defibrillation for ventricular fibrillation were included. We conducted a 24 months retrospective population-based analysis of the outcome in our population. RESULTS: Over a 24 month period, 446 people had non-traumatic cardiac arrest, and in all of them it was observed to be ventricular fibrillation. In a very few cases, the defibrillator operators were good Samaritans, acting voluntarily. Eighty-nine patients (about 19%) with ventricular fibrillation were successfully resuscitated, including eighteen who regained consciousness before hospital admission. CONCLUSION: Automated external defibrillators deployed in readily accessible, well-marked areas, are really very effective in assisting patients with cardiac arrest. However, it's quite true that, in the cases of survivors, most of our users had good prior training in the use of these devices.

Atrial fibrillation and pacing algorithms.

Pacing prevention algorithms have been introduced in order to maximize the benefits of atrial pacing in atrial fibrillation prevention. It has been demonstrated that algorithms actually keep overdrive atrial pacing, reduce atrial premature contractions, and prevent short-long atrial cycle phenomenon, with good patient tolerance. However, clinical studies showed inconsistent benefits on clinical endpoints such as atrial fibrillation burden. Factors which may be responsible for neutral results include an already high atrial pacing percentage in conventional DDDR, non-optimal atrial pacing site and deleterious effects of high percentages of apical ventricular pacing. Atrial antitachycardia pacing (ATP) therapies are effective in treating spontaneous atrial tachyarrhythmias, mainly when delivered early after arrhythmia onset and/or on slower tachycardias. Effective ATP therapies may reduce atrial fibrillation burden, but conflicting evidence does exist as regards this issue, probably because current clinical studies may be underpowered to detect such an efficacy. Wide application of atrial ATP may reduce the need for hospitalizations and electrical cardioversions and favorably impact on quality of life. Consistent monitoring of atrial and ventricular rhythm as well as that of ATP effectiveness may be extremely useful for optimizing device programming and pharmacological therapy.

Is the nocturnal fall in blood pressure reduced in essential hypertensive patients with metabolic syndrome?

OBJECTIVE: The aim of this study was to examine whether an impaired reduction in nocturnal blood pressure (BP), defined on the basis of two periods of ambulatory BP monitoring (ABPM), is present in hypertensive patients with metabolic syndrome, as defined by the NCEP criteria. METHODS: 460 grade 1 and 2 untreated essential hypertensives (mean age 45.9 +/- 11.9 years) referred for the first time to our outpatient hospital clinic underwent the following procedures: 1) medical history and physical examination; 2) repeated clinic BP measurements; 3) routine examinations; 4) ABPM over two 24-hour periods within 4 weeks. Metabolic syndrome was defined as at least three of the following alterations: increased waist circumference, increased triglycerides, decreased HDL-cholesterol, increased BP, or high fasting glucose. Nocturnal dipping was defined as a night-time reduction in average SBP and DBP >10% compared to average daytime values. RESULTS: The 135 patients with metabolic syndrome (group I) were similar for age, gender and known duration of hypertension to the 325 patients without it (group II). There were no significant differences between the two groups in average 48-hour, daytime, night-time SBP/DBP values and the percentage nocturnal SBP and DBP decrease (-17.7 / -15.7 vs. -18.4 / -16.2, p = ns). A reproducible nocturnal dipping (decrease in BP >10% from mean daytime in both ABPM periods) and non-dipping profile (decrease in BP < or =10% in both ABPM periods) was found in 74 (54.8%) and 29 (21.4%) in group I and in 169 (52.1%) and 73 (22.4%) in group II, respectively (p = ns); 32 patients (23.7%) in group I and 83 patients (25.5%) in group II had a variable dipping profile (p = ns). CONCLUSIONS: This study shows that no significant difference exists in nocturnal BP patterns, assessed by two ABPMs, in untreated essential hypertensive patients with metabolic syndrome compared to those without it.

Retinal microvascular changes and target organ damage in untreated essential hypertensives.

BACKGROUND AND PURPOSE: The clinical and prognostic significance of initial retinal alterations in hypertensive patients remains controversial. Therefore, we assessed the relationship of microvascular abnormalities with prognostically validated markers of target organ damage (TOD), such as left ventricular mass (LVM), carotid intima-media thickness (IMT) and microalbuminuria, in early stages of untreated essential hypertension. METHODS: A total of 437 consecutive, never-treated patients with grade 1 or 2 essential hypertension, referred to our outpatient clinic, underwent the following procedures: (1) clinical and routine laboratory examinations, (2) 24-h ambulatory blood pressure monitoring, (3) 24-h urine collection for microalbuminuria, (4) echocardiography, (5) carotid ultrasonography, (6) non-mydriatic retinography. Patients were divided into group I, with either a normal retinal pattern (n=65, 14.9%) or arteriolar narrowing (n=185, 42.4%) and group II with arteriovenous crossings (n=187, 42.7%). RESULTS: The two groups were similar for gender, body mass index, smoking habit, heart rate, clinic and ambulatory blood pressure (BP) values, while mean age was slightly but significantly higher in group II than in group I (47.6 +/- 10.7 versus 44.5 +/- 12.5 years, P=0.008). No differences occurred between the two groups in LVM index (101.8 +/- 18.5 versus 99.9 +/- 20.4 g/m), carotid IMT (0.67 +/- 0.12 versus 0.66 +/- 0.20 mm), urinary albumin excretion rate (14.4 +/- 27.7 versus 13.3 +/- 27.7 mg/24 h) as well as in the prevalence of LV hypertrophy (14.3 versus 14.0%), IM thickening and/or plaques (26.5 versus 27.2%) (both defined according to 2003 ESH-ESC guidelines) and microalbuminuria (10.1 versus 8.7%). Furthermore, the three different retinal artery patterns were similarly distributed among tertiles of LV mass index, IMT and urinary albumin excretion rate. CONCLUSIONS: These results show that: (1) a very large fraction (more than 80%) of untreated, recently diagnosed hypertensive patients have initial retinal microvascular abnormalities detectable by non-mydriatic retinography, (2) the presence of arteriovenous crossings is not associated with more prominent cardiac and extracardiac TOD, (3) fundoscopic examination has a limited clinical value to detect widespread organ involvement in early phases of grade 1 and 2 hypertension.

Metabolic syndrome and target organ damage in untreated essential hypertensives.

BACKGROUND: The prevalence and the relationship between metabolic syndrome, and target organ damage (TOD) in essential hypertensive patients has not been fully explored to date. OBJECTIVE: To investigate the association between metabolic syndrome, as defined by the ATP III report, and cardiac and extracardiac TOD, as defined by the 2003 ESH-ESC guidelines for management of hypertension, in a large population of never-treated essential hypertensives. METHODS: A total of 447 grade 1 and 2 hypertensive patients (mean age 46 +/- 12 years) who were attending a hypertension hospital outpatient clinic for the first time underwent the following procedures: (i) physical examination and repeated clinic blood pressure measurements; (ii) routine examinations; (iii) 24-h urine collection for microalbuminuria; (iv) 24-h ambulatory blood pressure monitoring; (v) echocardiography; and (vi) carotid ultrasonography. Metabolic syndrome was defined as involving at least three of the following alterations: increased waist circumference, increased triglycerides, decreased high-density lipoprotein cholesterol, increased blood pressure, or high fasting glucose. Left ventricular hypertrophy (LVH) was defined according to two different criteria: (i) 125 g/m in men and 110 g/m in women; (ii) 51 g/h in men and 47 g/h in women. RESULTS: The 135 patients with metabolic syndrome (group I) were similar for age, sex distribution, known duration of hypertension and average 24-h, daytime and night-time ambulatory blood pressure to the 312 patients without it (group II). The prevalence of altered left ventricular patterns (LVH and left ventricular concentric remodelling) was significantly higher in group I (criterion a = 30%, criterion b = 42%) than in group II (criterion a = 23%, criterion b = 30%, P < 0.05 and P < 0.01, respectively). A greater urinary albumin excretion (17 +/- 35 versus 11 +/- 23 mg/24 h, P = 0.04) was also found in group I compared to group II. There were no significant differences between the two groups in the prevalence of carotid intima-media thickening and plaques. CONCLUSIONS: These results from a representative sample of untreated middle-aged hypertensives show that: (i) the metabolic syndrome is highly prevalent in this setting and (ii) despite similar ambulatory blood pressure values, patients with metabolic syndrome have a more pronounced cardiac and extracardiac involvement than those without it.

Cardiovascular risk stratification according to the 2003 ESH-ESC guidelines in uncomplicated patients with essential hypertension: comparison with the 1999 WHO/ISH guidelines criteria.

BACKGROUND: The 2003 European Society of Hypertension/European Society of Cardiology (ESH-ESC) guidelines have recently proposed a new risk stratification scheme for estimating absolute risk for cardiovascular disease. At variance from the previous 1999 World Health Organization-International Society of Hypertension (WHO/ISH) guidelines, the new criteria include some additional risk factors such as obesity, abnormal high-density (HDL) or low-density lipoprotein (LDL) cholesterol levels and define a slight increase in creatinine and microalbuminuria as signs of target organ damage (TOD). OBJECTIVE: The aim of the study was to assess overall cardiovascular risk in uncomplicated hypertensives according to the 2003 ESH-ESC guidelines comparing this approach with the stratification scheme of the 1999 WHO/ISH guidelines. METHODS: Four hundred and twenty-five never-treated grade 1 and 2 essential hypertensive patients, referred for the first time to our outpatient clinic without diabetes mellitus, were included in the study. They underwent the following procedures: (i) repeated clinical blood pressure measurements; (ii) routine blood chemistry and urine analysis; (iii) electrocardiogram; (iv) 24-h urine collection for microalbuminuria; (v) echocardiogram; and (vi) carotid ultrasonogram. Risk was assessed according to both stratification schemes suggested by the 2003 ESH-ESC and 1999 WHO/ISH guidelines. RESULTS: According to the 2003 ESH-ESC guidelines, 15.5% of the 425 patients were considered at low added risk, 47.8% at medium added risk and 36.7% at high added risk; 146 patients (34.3%) were classified in the high-risk stratum because of at least one manifestation of TOD and 5.6% having three or more risk factors. The accuracy in detecting TOD of the combined approach with ultrasound procedures and microalbuminuria was approximately 10-fold higher than that provided by routine investigation. As a result of the 1999 WHO/ISH stratification scheme, 34.5% were low-risk, 34.4% medium-risk and 31.1% high-risk patients. CONCLUSIONS: Our findings show that: (i) more than one-third of uncomplicated grade 1 and 2 hypertensives seen in a outpatient hypertension hospital clinic have a high added risk according to the ESH-ESC scheme; (ii) classification of the patients in the high stratum is mainly influenced by the presence of TOD; (iii) the routine diagnostic work-up is a highly insensitive approach for the detection of TOD; (iv) the 2003 ESH-ESC guidelines stratify a higher proportion of hypertensive patients in the medium and high-risk groups than do the 1999 WHO/ISH guidelines.

Cardiovascular target organ damage in essential hypertensives with or without reproducible nocturnal fall in blood pressure.

OBJECTIVE: The clinical significance of classifying patients as dippers and non-dippers on the basis of a single period of ambulatory blood pressure monitoring (ABPM) has been questioned. The aim of this study was to evaluate the relationship between nocturnal dipping status, defined on the basis of two periods of ABPM, and cardiac and extracardiac target organ damage in essential hypertension. METHODS: A total of 375 never-treated essential hypertensive patients [mean 24-h blood pressure (BP) > or = 125/80 mmHg; mean +/- SD age 45.9 +/- 11.9 years] referred for the first time to our outpatient clinic underwent the following procedures: (i) repeated clinic BP measurements; (ii) blood sampling for routine chemistry examinations; (iii) 24-h urine collection for microalbuminuria; (iv) ABPM over two 24-h periods within 4 weeks; (v) echocardiography; and (vi) carotid ultrasonography. RESULTS: A reproducible nocturnal dipping (decrease in BP > 10% from mean daytime BP in both ABPM periods) and non-dipping profile (decrease in BP < or = 10% in both ABPM periods) was found in 199 (group I) and 79 patients (group II), respectively; 97 patients (group III) had a variable dipping profile. The three groups did not differ with regard to age, gender, body mass index, clinic BP, 48-h BP and heart rate. Left ventricular mass index, interventricular septum thickness, left atrium and aortic root diameters were significantly higher in group II compared with group I (mean +/- SD 108.5 +/- 19.5 versus 99.7 +/- 19.6 g/m, P < 0.05; 9.3 +/- 0.9 versus 9.1 +/- 0.9 mm, P < 0.05; 33.6 +/- 3.6 versus 32.2 +/- 3.7 mm, P < 0.01; 36.9 +/- 4.6 mm versus 35.5 +/- 4.6, P < 0.05, respectively). The smaller differences seen between groups II and III and between groups I and III were not statistically significant. The prevalence of left ventricular hypertrophy (defined as a left ventricular mass index > 134 g/m in men and > 110 g/m in women) was greater in group II (19%) than in group I (6%) (P < 0.05), whereas the differences between groups II and III and between groups I and III did not reach statistical significance. Differences among the three groups in the prevalence of carotid structural alterations (such as carotid plaques or intima-media thickening) were not statistically significant, and microalbuminuria had a similar prevalence in all three groups. CONCLUSIONS: Despite similar clinic and 48-h BP values, never-treated hypertensive patients with a persistent non-dipper pattern showed a significantly greater extent of cardiac structural alterations compared with subjects with a reproducible dipping pattern, but not those with a variable BP nocturnal profile. A non-dipping pattern diagnosed on two concordant ABPM periods instead of a single monitoring therefore represents a clinical trait associated with more pronounced cardiac abnormalities. Finally, in non-dipping middle-aged hypertensives, echocardiography appears to provide a more accurate risk stratification than carotid ultrasonography or microalbuminuria.

Trends in hypertension control and left ventricular hypertrophy over three years.

BACKGROUND: The aim of this study was to describe trends in blood pressure (BP) control and in the prevalence of left ventricular hypertrophy (LVH) during 3 years of follow-up in a representative sample of treated hypertensive patients seen in our out-patient hypertension hospital clinic. METHODS: Four hundred and sixty-four hypertensive treated patients who took part in a clinical survey at our out-patient clinic during the year 1997 and who had been submitted to a routine follow-up visit 3 years later were included in the study. All patients were subjected to the following procedures: an accurate medical history, physical examination, electrocardiogram, clinical BP measurement. For the diagnosis of LVH we used two different ECG criteria: the Solokow-Lyon voltage and the gender-specific Cornell voltage. RESULTS: During the first survey, 15% of treated patients had a clinical BP < 130/85 mmHg, 25.1% > or = 130/85 mmHg and < 140/90 mmHg, 33.6% > or = 140/90 and < 150/95 mmHg, 26.3% > or = 150/95 mmHg. The corresponding figures in the second survey were 19, 26.7, 33.2 and 21.1%, respectively. Overall, from the first to the second survey the prevalence of an effective BP control (< 140/90 mmHg) rose from 40.1 to 46.7% (p < 0.01). At baseline, 40 patients had ECG LVH (8.6%); at the second visit, LVH was found to have regressed in 19 of these patients. Among the 424 patients with a normal baseline electrocardiogram, 3 developed LVH during follow-up. Hence, the prevalence of LVH decreased from 8.6 to 5.1% (p < 0.01). In terms of treatment, the prevalence of combination therapy regimens increased from 68.6 to 79.7% (p < 0.05). CONCLUSIONS: This study demonstrates that in hypertensive patients managed in a hypertension hospital clinic, BP control improved during the long-term follow-up and that this trend was associated with a significant regression in ECG LVH.

Awareness of hypertension guidelines in general practice: a pilot study in Lombardy.

BACKGROUND: An adequate knowledge of hypertension guidelines by primary care physicians is a fundamental step for the improvement of the diagnosis and treatment of hypertension in the general population. The aim of this study was to evaluate, in a local survey in the northern area of Lombardy, the general practitioners' knowledge of the WHO/ISH guidelines. METHODS: A 10-item mail questionnaire based on the 1999 WHO/ISH hypertension guidelines was sent to a sample of 280 primary care physicians. The number of answers in agreement with the guidelines was used as a measure of guidelines knowledge, that was considered adequate if a correct answer to 6 out of 10 questions, in addition to an adequate definition of hypertension, was provided. RESULTS: The analysis was based on 83 returned questionnaires, that means a 29% response rate. Guidelines knowledge was adequate in 23.5% of the total study population and the mean score of correct answers was 5.5 points. A significant negative correlation (r = 0.27, p < 0.05) was observed between the mean score of knowledge and the physician's age. CONCLUSIONS: In a sample of primary care physicians from a northern region of Italy, the hypertension guidelines knowledge is inadequate; the reasons and the extent of this poor awareness will require further studies.