Assessment of Myocardial Contractility by SonR Sensor in Patients Undergoing Cardiac Resynchronization Therapy.

BACKGROUND: SonR sensor signal correlates well with myocardial contractility expressed in terms of left ventricular (LV) dP/dt max. The aim of our study was to evaluate the changes in myocardial contractility during isometric effort in heart failure patients undergoing cardiac resynchronization therapy (CRT) with right atrial SonR sensor. METHODS: Thirty-one patients (19 men, 65 ± 7 years, LV ejection fraction [LVEF] 28% ± 5%, in sinus rhythm) were implanted with a CRT-defibrillator (CRT-D) device equipped with SonR sensor, which was programmed in VVI mode at 40 beats/min. Twenty-four hours after implantation, each patient underwent a noninvasive hemodynamic evaluation at rest and during isometric effort, including: (1) measurement of beat-to-beat endocavitary SonR signal; (2) echocardiographic assessment; and (3) continuous measurement of blood pressure with Nexfin method (BMEYE, Amsterdam, the Netherlands). The following contractility parameters were considered: (1) mean value of beat-to-beat SonR signal; (2) mean value of LV dP/dt by Nexfin system; and (3) fractional shortening (FS) by echocardiography. RESULTS: At the third minute of the isometric effort, mean value of SonR signal significantly increased from baseline (P < 0.001). Similarly, mean value of both LV dP/dt by Nexfin and FS significantly increased compared to the resting condition (P < 0.001; P < 0.001). While in 27 (88%) patients SonR signal increased at the third minute of the isometric effort, in four (12%) patients SonR signal decreased. In these patients, both LV dP/dt by Nexfin and FS consensually decreased. CONCLUSIONS: In CRT patients, SonR sensor is able to detect changes in myocardial contractility in a consensual way like noninvasive methods such as Nexfin system and echocardiography.

Acute insulin resistance assessed by the homeostatic model assessment in acute coronary syndromes without previously known diabetes.

We assessed the incidence and the prognostic role for early death of acute insulin resistance (by means of homeostatic model assessment [HOMA] index) in 1350 patients with acute coronary syndrome (ACS) consecutively admitted to our intensive cardiac care unit (ICCU). The incidence of HOMA positivity was 5% (68 of 1350), with the highest percentage of HOMA positivity among ST-segment elevation myocardial infarction (STEMI). Patients with HOMA positivity showed a higher body mass index (P = .003), lower values of admission and discharge left-ventricular ejection fraction (LVEF; P < .001 and P = .003, respectively), and higher levels of peak troponin I (Tn I; P < .001). The HOMA index was an independent predictor of early death (odds ratio 1.724, 95% confidence interval 1.252-2.375, P = .001). In patients with ACS and without previously known diabetes, acute insulin resistance (HOMA index) is associated with a larger myocardial damage (ie, higher values of peak Tn I and lower LVEF) and a greater inflammatory activation (indicated by correlation with leukocyte count). The HOMA positivity was an independent predictor of in-ICCU mortality.

Intraaortic balloon pump: incidence and predictors of complications in the Florence registry.

BACKGROUND: The intraaortic balloon pump (IABP) is the most commonly used mechanical circulatory support for patients with acute coronary syndromes and cardiogenic shock. Nevertheless, IABP-related complications are still frequent and associated with a poor prognosis. HYPOTHESIS: To prospectively assess the incidence and predictors of complications in patients treated with IABP. METHODS: A total of 481 patients treated with IABP were prospectively enrolled in our registry (the Florence Registry). At multivariable logistic regression analysis the following variables were independent predictors for complications (when adjusted for age >75 years, eGFR and time length of IABP support): use of inotropes (OR 2.450, P < 0.017), nadir platelet count (1000/µL step; OR 0.990, P < 0.001), admission lactate (OR 1.175, P = 0.003). Nadir platelet count showed a negative correlation with length of time of IABP implantation (r-0.31; P < 0.001). A nadir platelet count cutoff value of less than 120,000 was identified using a receiver operating characteristic (ROC) curve for the development of complications (area under the curve [AUC] 0.70; P < 0.001). RESULTS: Complications were observed in the 13.1%, among whom 33 of 63 showed major bleeding. The incidence of complications was higher in patients aged >75 years (P = 0.015) and in those who had an IABP implanted for more than 24 hours (P = 0.001). Patients with complications showed an in Intensive Cardiac Care Unit (ICCU) mortality higher than patients who did not (44.4% vs 17.2%, P < 0.001). CONCLUSIONS: In consecutive patients treated with IABP support, the degree of hemodynamic impairment and the decrease in platelet count were independent predictors of complications, whose development was associated with higher in-ICCU mortality.

A new post-PCI scoring system for in-hospital mortality in STEMI patients.

OBJECTIVE: To develop a scoring system for predicting in-hospital mortality among ST-elevation myocardial infarction (STEMI) patients submitted to percutaneous intervention (PCI) on intensive cardiac care unit admission by using early and readily available clinical, angiographic and laboratory data. DESIGN: Prospective monocentric observational study in which we used discriminant analysis to develop a final scoring system, with prospective validation. SETTING: Intensive cardiac care unit in Florence, a tertiary center. POPULATION: Five hundred and fifty-eight unselected patients with STEMI (group A) consecutively admitted from 1 January 2004 to 31 December 2006. A control group (group B) comprising 183 STEMI patients admitted from 1 January 2007 to 30 September 2007. MAIN OUTCOMES AND MEASURES: In-hospital death. RESULTS: In group A the discriminant variables were admission Killip class, admission lactic acid, admission ejection fraction, admission troponin I (TnI), admission hemoglobin (Hb), ST-segment reduction post-PCI, systolic blood pressure on admission and chronic renal failure. We elaborated a scoring system, the Florence admission STEMI risk score, which shows an agreement of 95.7% between the observed and the estimated outcome on a statistical basis in the survival and death subgroups. We applied this score to group B (C statistics = 0.986). CONCLUSION: The Florence admission STEMI risk score incorporates anamnestic (chronic renal failure), laboratory (lactic acid, TnI and Hb), procedural and post-procedural data (ST-segment reduction post-PCI, Killip class) as well as data strictly related to infarct size (ejection fraction, TnI). This scoring system is likely to be a simple and practical tool at the bedside for risk evaluation in patients with STEMI submitted to primary PCI.

Prognostic role of insulin resistance as assessed by homeostatic model assessment index in the acute phase of myocardial infarction in nondiabetic patients submitted to percutaneous coronary intervention.

BACKGROUND AND OBJECTIVES: Little information is available on the relation between insulin resistance and acute myocardial infarction. METHODS: In 253 consecutive nondiabetic patients with ST elevation myocardial infarction (STEMI) submitted to percutaneous coronary intervention, we assessed the prevalence of insulin resistance by homeostatic model assessment (HOMA) index and its prognostic role in early and late mortality. RESULTS: Insulin resistance was detectable in 52.9% of patients. Anterior STEMI was more frequent in insulin-resistant patients (P = 0.040), who showed higher values of probrain natriuretic peptide (P = 0.010), creatinine (P < 0.001), creatinine phosphokinase and creatinine phosphokinase-MB (MB, isoenzyme present in the myocardium; P = 0.016 and P = 0.003, respectively). At backward stepwise logistic regression analysis, the following variables were independent predictors for intra-intensive cardiac care unit mortality: HOMA index [hazard ratio 1.40; 95% confidence interval (CI) 1.02-1.95; P = 0.049]; C-peptide (hazard ratio 3.14; 95% CI 1.40-24.80; P = 0.001) and lactic acid (hazard ratio 2.50; 95% CI 1.41-4.44; P = 0.002). At long-term follow-up (Cox regression analysis), neither fasting glycaemia nor HOMA index resulted in predictors for mortality. CONCLUSION: In nondiabetic STEMI patients submitted to percutaneous coronary intervention, insulin resistance, as assessed by HOMA index, is quite common and helps in the early prognostic stratification, as it represents an independent predictor of in-hospital mortality.

Systemic arterial waveform analysis and assessment of blood flow during extracorporeal circulation.

BACKGROUND: The pressure recording analytical method (PRAM) is a method for real-time beat-to-beat quantification of peripheral blood flow based on the analysis of arterial waveform morphology. Since PRAM can be implemented in any conditions of flow, whether physiological or artificial, we assessed its accuracy in patients undergoing cardiac surgery during extracorporeal circulation (ECC), using the roller-pump device as the reference gold standard. METHODS: We prospectively studied 32 patients undergoing elective coronary surgery. Flow values obtained by PRAM from the radial artery were compared with simultaneous values by thermodilution in physiological conditions of flow and with the roller-pump device readings during ECC. RESULTS: Before and after ECC, the overall estimates of flow measured by PRAM closely agreed with thermodilution (mean difference 0.07 +/- 0.40 L/min). During ECC, PRAM estimates of flow also closely correlated with simultaneous pump readings (mean difference 0.11 +/- 0.33 L/min). At time of weaning from ECC, two patterns of hemodynamic adaptation were documented by PRAM following resumption of cardiac contraction: in most patients (n =26; 80%), cardiac output (CO) was stable (reduction < or = 10% compared to the steady ECC phase); six patients (20%) showed a fall in CO exceeding 10% and up to 38%. CONCLUSIONS: PRAM provided accurate, continuous quantification of peripheral blood flow during each phase of cardiac surgery, including ECC, and allowed early recognition of patients with low CO during weaning from the pump.