Left Ventricular Mechanics in Functional Ischemic Mitral Regurgitation in Acute Inferoposterior Myocardial Infarction.

UNLABELLED: Ischemic mitral regurgitation (MR) is an established adverse prognostic factor after myocardial infarction (MI). Functional ischemic mitral regurgitation in acute phase of MI remains under-investigated due to its often transient and dynamic nature. We aimed to assess left ventricular (LV) mechanics by speckle-tracking echocardiography in acute inferoposterior MI and ischemic mitral regurgitation (MR). METHODS: Sixty-nine patients with no structural cardiac valve abnormalities and first acute inferoposterior MI were prospectively enrolled into the study. Two-dimensional transthoracic echocardiography for regional myocardial function and valve assessment was performed within 48 hours of presentation after reperfusion therapy (percutaneous coronary intervention). Based on degree of MR, patients were divided into no significant MR (NMR) group (N = 34, with no or mild (grade 0-I) MR) and ischemic MR (IMR) group (N = 35, with grade ≥2 MR). Thirty-five age- and gender-matched healthy individuals served as a normal reference group. Offline 2D speckle tracking analysis was performed with GE EchoPAC software. RESULTS: LV ejection fraction and longitudinal myocardial deformation parameters were significantly better in healthy subjects, but did not differ between both study groups. All circumferential myocardial deformation parameters were significantly worse in IMR group compared to healthy subjects and NMR group. Global, basal, and mid-ventricular radial strain was significantly lower in IMR group compared to both-healthy subjects and NMR group. CONCLUSION: Ischemic mitral regurgitation in acute inferoposterior MI is associated with worse radial and circumferential LV deformation parameters assessed by 2D speckle tracking echocardiography.

Prognosis of in-hospital myocardial infarction course for diabetic and nondiabetic patients using a noninvasive evaluation of hemodynamics and heart rate variability.

BACKGROUND AND OBJECTIVE: The objective of our study was to investigate whether the combination of markers of heart rate variability (HRV) and impedance cardiography (ICG) help evaluate the risk of in-hospital death, ventricular arrhythmia, or complicated course secondary to myocardial infarction (STEMI) and to clarify whether combined analysis of HRV and ICG improve prognosis of STEMI, comparing 3 groups: 1) diabetic, 2) nondiabetic, and 3) diabetes-unselected patients. MATERIAL AND METHODS: The parameters reflecting heart rate variability and central hemodynamics were estimated from a 24-hour synchronic electrocardiogram and thoracic impedance signal recordings in 232 patients (67 diabetic) on the third day after myocardial infarction. Logistic regression analysis was used to determine the predictors of selected outcomes. Different prognostic models were compared with the receiver operating characteristic curve analysis. RESULTS: The model consisting of low- and high-frequency power ratio (LF/HF) and cardiac output (CO) was elaborated for the prognosis of in-hospital death in the group 3 (odds ratios [ORs] were 9.74 and 4.85, respectively). Very low-frequency power (VLF), cardiac index (CIN), and cardiac power output (CPO) were the predictors of ventricular arrhythmia in the group 2 (ORs of 1.005, 5.09, and 66.7, respectively) and the group 3 (ORs of 1.004, 3.84, and 37.04, respectively). The predictors of the complicated in-hospital course in the group 1 were the baseline width of the minimum square difference triangular interpolation of the highest peak of the histogram of all NN intervals (TINN) and stroke volume (SV) (ORs of 1.006, and 1.009, respectively); in the group 2, the mean of the standard deviations of all NN intervals for all 5-minute segments of the recording (SDNN index) and CPO (ORs of 1.06 and 2.44, respectively); and in the group 3, SDNN index, VLF, LF/HF, CIN (ORs of 1.04, 1.004, 2.3, and 3.49, respectively). CONCLUSIONS: The patients with decreased HRV and low estimates of central hemodynamics evaluated by ICG are at an increased risk of the adverse in-hospital course of STEMI. The combined analysis of HRV and ICG hemodynamic estimates contributes to the risk assessment of the complicated in-hospital course of STEMI, in-hospital hemodynamically significant ventricular arrhythmia, and in-hospital death secondary to STEMI. The in-hospital prognostic value of the combined estimates of HRV and ICG is lower in the STEMI patients with diabetes mellitus as compared with the nondiabetic patients.

Impedance cardiography and heart rate variability for long-term cardiovascular outcome prediction after myocardial infarction.

BACKGROUND AND OBJECTIVE: The objective of our study was to evaluate the predictive power of a combined assessment of heart rate variability (HRV) and impedance cardiography (ICG) measures in order to better identify the patients at risk of serious adverse events after ST-segment elevation myocardial infarction (STEMI): all-cause or cardiac mortality (primary outcomes) and in-hospital recurrent ischemia, recurrent nonfatal MI, and need for revascularization (secondary outcomes). MATERIAL AND METHODS: A total of 213 study patients underwent 24-hour electrocardiogram (used for HRV analysis) and thoracic bioimpedance monitoring (used for calculation of hemodynamic measures) immediately after admission. The patients were examined on discharge and contacted after 1 and 5 years. Cox regression analysis was used to determine the predictors of selected outcomes. RESULTS. The standard deviation of all normal-to-normal intervals (SDNN) and cardiac power output (CPO) were found to be the significant determinants of 5-year all-cause mortality (SDNN ≤ 100.42 ms and CPO ≤ 1.43 W vs. others: hazard ratio [HR], 11.1; 95% CI, 4.48-27.51; P<0.001). The standard deviation of the averages of NN intervals (SDANN) and CPO were the significant predictors of 5-year cardiac mortality (SDANN ≤ 85.41 ms and CPO ≤ 1.43 W vs. others: HR, 11.05; 95% CI, 3.75-32.56; P<0.001). None of the ICG measures was significant in predicting any secondary outcome. CONCLUSIONS: The patients with both impaired autonomic heart regulation and systolic function demonstrated by decreased heart rate variability and impedance hemodynamic measures were found to be at greater risk of all-cause and cardiac death within a 5-year period after STEMI. An integrated analysis of electrocardiogram and impedance cardiogram helps estimate patient's risk of adverse outcomes after STEMI.

[Autonomic heart rhythm regulation and its alteration in myocardial infarction and diabetes mellitus]. / Autonomine sirdies ritmo reguliacija bei jos pokyciai sergant miokardo infarktu ir cukriniu diabetu.

Coronary heart disease and diabetes mellitus are closely linked together. Myocardial infarction is the most severe stage of coronary heart disease. Natural course and prognosis of acute myocardial infarction is much worse in patients with diabetes mellitus as compared to age- and gender-matched non-diabetic controls. Many studies have been made to improve evaluation and risk stratification of such patients. A promising area is investigation of autonomic cardiovascular nervous system and its alteration during the myocardial infarction and diabetes mellitus. Parasympathetic and sympathetic effects on heart rate have been studied at various levels for many years, but their mechanisms are complex and not fully elucidated. This article overlooks the recent studies on the mechanisms of autonomic cardiovascular regulation and its alteration in myocardial infarction and diabetes mellitus. Modern methods to investigate autonomic regulation of the heart as well as possible interventional and medical therapies that modulate cardiac autonomic tone are also reviewed. In order to better understand the origin and evolution of pathological changes in autonomic regulation during the above-mentioned diseases, we have also presented a brief view on some functional aspects of natural cardiac pacemaker, the neuroanatomy of cardiac autonomic innervation, and mechanisms of normal heart rhythm regulation.

Characteristics and management of acute heart failure patients in a single university hospital center.

OBJECTIVE: To evaluate the causes of acute heart failure, complications, management, and outcomes. MATERIAL AND METHODS: A total of 200 patients with diagnosed de novo acute heart failure (27.5%) or worsening chronic heart failure (72.5%) were treated at the Department of Cardiology, Hospital of Kaunas University of Medicine, which was participating in the Euro Heart Failure Survey-II (EHFS-II). The patients were divided into five groups: 1) chronic decompensated heart failure (66.0%); 2) pulmonary edema (13.0%); 3) hypertensive heart failure (7.5%); 4) cardiogenic shock (11.0%); and 5) right heart failure (2.5%). RESULTS: Hypertensive and coronary heart diseases were the most common underlying conditions of acute heart failure. Noncompliance with the prescribed medications was present as the most frequent precipitating factor in more than half of the cases. Left ventricular ejection fraction of >45% was found in 28.64% of cases. Intravenous diuretics (74.5%), nitrates (44.0%), and heparin (71.0%) were the most widely used in the acute phase. At discharge from hospital, 96.69% of patients were given diuretics; 80.11%, angiotensin-converting enzyme inhibitors; and 62.43%, beta-blockers. The mean duration of inhospital stay was 13 days; death rate was 9.5%: after 3 months and 12 months, it was 7.5% and 11.5%, respectively. CONCLUSION: Preserved systolic function, multiple concomitant diseases, and high mortality rates were observed in a substantial proportion of the patients hospitalized due to acute heart failure. The management of the patients in a university hospital center was performed in accordance with the international guidelines.

[Electrical defibrillation and cardioversion]. / Elektrine sirdies defibriliacija ir kardioversija.

Defibrillation and cardioversion are techniques in which a short electric impulse is administered to the heart in order to restore its normal rhythm. During cardioversion electric impulse is synchronized to the QRS on electrocardiogram. During defibrillation electric current passes through the heart in any phase of electric heart cycle. This mode of treatment is rather new - Lown et al. started to use it in a clinical practice in 1962. During defibrillation or cardioversion electric current goes from negative to positive electrode of defibrillator and passes the heart on its way. This induces transmembrane potential in myocardium cells and results in synchronic depolarization of all myocardium. The pathophysiology of defibrillation is explained by critical mass hypothesis as well as the upper limit of vulnerability hypothesis. The success of defibrillation depends on many factors, such as the location and size of electrodes, the type of defibrillator, the morphology of electric impulse, transthoracic impedance, the type and duration of arrhythmia. This procedure can be performed only on unconscious patient. The possible complications of the procedure can be disturbances in heart rhythm and conduction, the changes in arterial blood pressure, the damage to the myocardium, embolia, pulmonary edema and others. This article describes the mechanism of action of defibrillation and cardioversion, indications for this procedure, the technique and methods of defibrillation and cardioversion, the factors, responsible for the efficacy of the procedure and possible complications of defibrillation.

Mitral valve prolapse: diagnosis, treatment and natural course.

This article analyzes data obtained from the medical records of the patients with primary mitral valve prolapse. The study population was the patients admitted to Kaunas University of Medicine Heart Center (KUMHC) between 1999 and 2003. The objective of our study was to analyze the natural course of mitral valve prolapse, complications and their frequency, treatment strategy in KUMHC, as well as to review the results of surgical treatment. We gathered data from the medical records of 160 patients and analyzed their age, medical history, complications, comorbidities, functional status and echocardiographic parameters. Patients who underwent mitral valve surgery were followed 7.9+/-8.4 months after procedure. On average, 32+/-14 patients with primary mitral valve prolapse were treated at KUMHC annually. Their mean age was 48.4+/-16.5 years, 44.4% of them were male. The most frequent complications of mitral valve prolapse were > or =II degrees mitral regurgitation (78.4%), various cardiac arrhythmias (68.1%) and heart failure of > or =II NYHA class (79%). Surgical treatment was recommended for 64 (40%) KUMHC patients with primary mitral valve prolapse. Surgical treatment was applied in 44 (28.1%) of study patients. The patients, who were recommended surgical treatment, were older (mean age 53.2+/-11.9 years, p<0.05) and predominantly male (62.5%, p<0.05) as compared to medically managed patients. The heart failure (62.5% had NYHA class III or IV), severe mitral regurgitation (95.3% had mitral regurgitation of > or =III degrees ) and worse left ventricle function (15% had ejection fraction of <50%) were more frequent in this group as compared to medically managed patients (all p<0.05). During the last five years the number of hospitalized patients with primary mitral valve prolapse increased 3.2 times, the number of mitral valve surgical procedures among these patients increased 2.8 times, and the number of mitral valve repair increased 15.8 times. 56.8% of patients had uncomplicated postoperative course. The most frequent postoperative complication was new arrhythmias and/or conduction disturbances. 1 patient died in early postoperative period. There was significant decrease in left ventricle and left atrium size and the severity of mitral regurgitation 2 to 6 months after mitral valve surgery. These positive changes remained during all study period. Taking in the consideration the large number of mitral valve repair procedures and good outcomes, the low postoperative mortality of the surgical mitral valve prolapse treatment in KUMHC, we can strongly recommend surgical treatment for the patients with severe mitral regurgitation secondary to mitral valve prolapse.