RVoutflow tract pacing versus RV Apical pathophysiologic Effects and prognostic implications

Right ventricular apical pacing has been reported to be associated with adverse haemodynamic effects and alternative sites of pacing have been recommended. On the other hand RV septal pacing was claimed to be more physiological. The present work is intended to compare the classic right ventricular apical DDD pacing to RV outflow tract [RVOT] pacing in both normal and diseased hearts. We studied 30 patients [pts] with complete heart block [CHB]. Fourteen pts [Group I] had no underlying heart disease [8M and 6F with mean age 64.1 +/- 6.4, range 54-76 years] and 16 [Group II] had heart disease [10M, 6F, with mean age 67.5 +/- 8.9, range 58-86 years] including DCM in 12, 1HD in 3 and RHD in Ipt. Right ventricular apical pacing was conducted in 7pts from group I and 8pts from group II. RVA was conducted in 7pts of group I and 8pts of group II. Besides clinical evaluation, all pts were subjected to 2D echo before, and 6 months after pacing. Echo parameters studied included LVEDD, LVESD, EF% and CO with effects expressed in terms of% changes in various parameters. Compared to RVA pacing RVOT pacing in group I [pts with normal heart] induced insignificant% decrease in LVEDD [2.4 +/- 4.8vs 8.6 +/- 9.3, p value =0.146] or LVESD [4.6 +/- 7.8vs 8.3 +/- 6.0,p value =0.113] and insignificant increase in EF [2.4 +/- 4.6vs 0.42.6, p value =0.113] and CO [2.8 +/- 8.0vs 3.3 +/- 3.5, p value =0.08]. However in RVOT pacing in group II [pts with disease heart] induced significantly greater% decrease in LVEDD [3.0 +/- 2.8vs 1.2 +/- 2.3, p=0.005] in LVESD [3.7 +/- 0.9vs 2.5 +/- 2.3, p=0.000], and significantly greater% increase in EF [8.9 +/- 3.3vs I.7 +/- 1.2,p=0.001] and CO [5.8 +/- 9.6vs 10.7 +/- 18.3, p=0.04] in comparison to RVA pacing in group II In the presence of underlying cardiac dysfunction, DDD pacing by RVOT lead is hemodynamically more advantageous to classic RV apical pacing in terms of improving dimensions and enhancing systolic function. We recommend RVOT pacing in the presence of underlying HD to avoid the so called pacing-induced cardiomyopathy.

Cardiac function in chronic obstructive Airway disease patients A comparative study between tissue doppler imaging and radionuclide study

Adequate assessment of RV function is very important in haemodynamically unstable critically ill patients as the presence of significant RV dysfunction may alter therapy and is of prognostic significance. The continuously present derangements of cardiac function in those patients hinder the application of invasive monitoring or even non invasive imaging.Modern technology however namely tissue Doppler imaging and nuclear scintigraphic techniques have permitted accurate and reproducible indices of global and regional myocardial function. The present work is intended to assess cardiac function in chronic obstructive air way disease patients presented to the ICU with acute respiratory failure, using the technique of nuclear imaging compared with the golden st and ard technique of 2-dimensional echocardiography, also studying the systolic and diastolic myocardial function using the newly developed technique of tissue Doppler imaging through studying 15 patients [9 females and 6 males] mean age 61 +/- 6.8 years. All having acute respiratory failure on top of COPD. Twelve healthy subjects were studied [7 females, 5 males] mean age 46.1 +/- 13.7 years serving as a control group.Following clinical evaluation and lab measurements. All patients and control group were subjected to myocardial perfusion imaging with SPECT[99m] Tc Sesta MIBi using 25-30 MCi of [99m] Tc injected intravenously with first pass acquisition is acquired within six hours from injection to get the myocardial perfusion and function in the acute state. Echo Doppler study with color flow mapping was conducted using 3 st and ard views with ATL MDI 5000 echocrdiography. The following echo parameters were obtained: Left ventricular end diastolic and end systolic volumes, ejection fraction obtained according to the simpson's method as well as all systolic and diastolic parameters.Tissue Doppler imaging including velocities and time intervals. Scintigraphically patients were assessed using cardiac volumes and perfusion. The right side was assessed using volumes and ejection fraction. Both techniques were repeated at an average of seven days [7.3 +/- 1.5 day]

Aortic root distensibility in patients with coronary artery disease

An important determinant of myocardial performance, namely cardiac afterload is largely dependent upon aortic root distensibility [AD], peripheral arterial resistance and end systolic wall stress. The latter can be reliably measured by using m-mode and 2-D echo whereas AD used to be a neglected parameter. In patients with ischaemic heart disease, the question always arises whether AD could in a way or another predict coronary arterial pathology /= 200 and /or LDL >130mg/dl in 21pts and HTN in 17pts. Following clinical evaluation including 12 lead ECG, m-mode and 2-D echocardiography, all pts underwent diagnostic CA and were subjected to transoesophageal echocardiography [TEE] using phased array multiplane 32 elements transducer [5MHz] mounted on the tip of 100cm gastroscope with Acuson Sequoia C256 system. Transoesophageal [TEE] was done while the pts in the left lateral position. The studies were recorded on videotapes for off-lines analysis. Images of the aortic root were obtained in an angle of about 120 degrees. Aortic root was measured in systole [maximal diameter] and diastole [electrocardiographic Q-wave] 3cm from cusps insertion using the trailing edge-to-leading edge method. Measurements were taken in 3 cycles and the mean value was taken, with the difference in diameter delta d as a measurement of aortic root excursion, delta p as the pulse pressure, and d=diastolic aortic root diameter. AD was expressed as =2xdelta d / delta pxd. According to CA, pts were divided into those with diseased coronary arteries 74.4% and those with a normal CA 25.6%. Compared to the normal CA group, AD was insignificantly different from that into pts with diseased CA 23.9 vs 21.4, p value = 0.573. Patients were then stratified into two groups with an age of 50yrs, SBP of 130mmHg, DBF of 80mmHg, serum cholesterol >200 and /or LDL >/= 130mg/dl and presence of DM serving as arbitrary dividing limits

Blood glucose level as a risk predictor of non-diabetic patients admitted with acute myocardial infarction

Hyperglycemia is associated with increased levels of inflammatory markers in patients with acute myocardial infarction and in acutely ill patients in general. The aim of the study is to determine whether admission blood glucose level can be used as a risk predictor in acute myocardial infarction in non-diabetic patients. Follow up of all non-diabetic patients admitted to I.C.U, with a definitive diagnosis of acute myocardial infarction between December 2002 to February 2005 was carried out. A total of 90 patients were studied and followed for six months. Glycosated haemoglubin was done to exclude previously high blood sugar. The studied patients were randomized according to the outcome trying to correlate it with the level of blood sugar during admission. The mean age was 55 years [range 36-83 years], and male to female ratio was 6.5:1. Admission blood glucose level was significantly higher in patients who developed heart failure, reinfarction and those who died, 8.9 mmol/l versus 7.3 mmol/l, 8.3 mmol/l versus 7.1 nomol/l and 9.4 mmol/l versus 7.7 mmol/l [P=0.01, .13, .003 respectively]. Old age was also significantly associated with poor outcome, at the same time there was significant relation between the peak cardiac enzyme [creatinine phosphokinase] level and worse outcome. Admission blood glucose level after acute myocardial infarction [AMI] is an independent predictor of long term mortality and morbidity without known diabetes. Patients with unknown diabetes and high glucose level in admission with AMI have higher rate of complication, a point that may serve to identify subjects at high risk

Efficacy of recombinant human erythropoietin in critically ill anaemic septic patients

To investigate the erythropoietic response to high dose of a weekly dosing schedule of recombinant human erythropoietin [rHuEPO] in critically ill anaemic septic patients, and to determine whether the administration of rHuEPO would reduce the number of red blood cell [RBC] transfusions required and whether would affect clinical course and final outcome or not. A prospective, randomized, controlled single center study. Critical Care Department [medical/surgical ICU], Cairo University Hospital. A total of 60 patients who were admitted to the intensive care unit [ICU] and met the eligibility criteria were enrolled into the study [30 into the rHuEPO group, 30 into the control group]. Patients were randomized to receive either rHuEPO or not. The study drug [40.000 units of rHuEPO] was administrated by subcutaneous injection beginning on ICU day 2 and continued once weekly for a minimum of 2 doses or until ICU discharge [for patients with ICU length of stay >2 weeks] up to a total of 4 doses. CBC, reticulocytic count, iron variables, APACHE II, SOFA scores were measured at baseline and subsequently thereafter every 3rd day until ICU discharge or death or up to a total of 28 days. The EPO treated group showed significant increases in reticulocytic count compared with baseline [P<0.001] as well as with the control group [P<0.006]. The EPO-treated group exhibited also significant increases in Hb concentration compared with baseline [P<0.001] as well as with the control group [P<0.03]. All patients in the control group received RBC transfusion [100%] while only [83.33%] of the patients who received rHuEPO were transfused. Concerning the in hospital clinical course, the EPO treated group showed significant decreases in their APACHE II score during the study period compared with baseline [P<0.001] as well as with the control group [P<0.05], the EPO treated group showed also no significant difference in their SOFA score during the study period compared with baseline [P=0.923], however, the control group exhibited continous and significant increase in their SOFA score throughout the study period compared with baseline [P<0.003]. There was no significant difference in the final outcome [i.e. recovery, mortality or morbidity] [P:0.337, P: 0.286 respectively]. The administration of rHuEPO to critically ill anaemic septic patients is effective in raising their reticulocytic counts, Hb concentrations and in reducing the total number of units of RBCs they require. In addition there was a trend toward better inhospital clinical course, increased recovery and decreased mortality in rHuEPO group