Dobutamine and nitroprusside infusion in patients with severe congestive heart failure: hemodynamic improvement by discordant effects on mitral regurgitation, left atrial function, and ventricular function

Pulmonary artery wave intensity analysis in pulmonary hypertension associated with heart failure and reduced left ventricular ejection fraction

Wave intensity analysis (WIA) uses simultaneous changes in pressure and flow velocity to determine wave energy, type, and timing of traveling waves in the circulation. In this study, we characterized wave propagation in the pulmonary artery in patients with pulmonary hypertension associated with left-sided heart disease (PHLHD) and the effects of dobutamine. During right heart catheterization, pressure and velocity data were acquired using a dual-tipped pressure and Doppler flow sensor wire (Combowire; Phillips Volcano), and processed offline using customized Matlab software (MathWorks). Patients with low cardiac output underwent dobutamine challenge. Twenty patients with PHLHD (all heart failure with reduced left ventricular ejection fraction) were studied. Right ventricular systole produced a forward compression wave (FCW), followed by a forward decompression wave (FDW) during diastole. Wave reflection manifesting as backward compression wave (BCW) following the FCW was observed in 14 patients. Compared to patients without BCW, patients with BCW had higher mean pulmonary artery pressure (28.7 ±  6.12 vs. 38.6 ± 6.5 mmHg, p = 0.005), and lower pulmonary arterial capacitance (PAC: 2.88 ± 1.75 vs. 1.73 ± 1.16, p = 0.002). Pulmonary vascular resistance was comparable. Mean pulmonary artery pressure of 34.5 mmHg (area under the curve [AUC]: 0.881) and PAC of 2.29 mL/mmHg (AUC: 0.833) predicted BCW. The magnitude of the FCW increased with dobutamine (n = 11) and correlated with pulmonary artery wedge pressure. Wave reflection in PHLHD is more likely at higher pulmonary artery pressures and lower PAC and the magnitude of reflected waves correlated with pulmonary artery wedge pressure. Dobutamine increased FCW but did not affect wave reflection.

Sodium nitroprusside in acute heart failure: A multicenter historic cohort study

AIMS

Despite evidence of hemodynamic benefit of sodium nitroprusside (SNP) treatment for acute heart failure (AHF), there are limited data about its efficacy and safety. This study aimed to assess the effectiveness and safety of SNP treatment, to explore the impact of N-terminal pro-B natriuretic peptide (NT-proBNP) reduction on clinical endpoints and to identify possible predictors of clinical response.

METHODS AND RESULTS

Multicenter retrospective cohort study of 200 patients consecutively admitted for AHF in 2 Italian Centers. Primary endpoint was the reduction of NT-proBNP levels ≥25% from baseline values within 48 h from the onset of SNP infusion. Secondary and safety endpoints included all-cause mortality, rehospitalization for HF at 1, 3 and 6 months, length of hospital stay (LOS) and severe hypotension. 131 (66%) patients experienced a NT-proBNP reduction ≥25% within 48 h from treatment onset, irrespective of initial systolic blood pressure (SBP). Left ventricular end diastolic diameter (LVEDD) was the only independent predictor of treatment efficacy. Patients who achieved the primary endpoint (i.e., 'responders') had lower LOS (median 15 [IQR:10-27] vs 19 [IQR:12-35] days, p-value = 0.033) and a lower incidence of all-cause mortality and rehospitalization for HF at 1 and 3 months compared to "non responders" (p-value <0.050). Severe hypotension was observed in 10 (5%) patients, without any adverse clinical consequence.

CONCLUSION

SNP is a safe and effective treatment of AHF, particularly in patients with dilated left ventricle. Reduced NT-proBNP levels in response to SNP is associated to shorter LOS and lower risk of 1- and 3-month re-hospitalizations for HF.

CLINICAL TRIAL REGISTRATION

http://www.

CLINICALTRIALS

gov. Unique identifier: NCT05027360.

Does the volume overload exaggerate the severity of mitral regurgitation in patients with decompensated heart failure?

Background/aim

Diagnosing and managing functional mitral regurgitation (MR) is often challenging and requires an integrated approach including a comprehensive echocardiographic examination. However, the effects of volume overload on the echocardiographic assessment of MR severity are uncertain. The purpose of this study was to weigh the effects of volume overload in the echocardiographic assessment of MR severity among patients with heart failure (HF).

Materials and methods

Twenty-nine patients with decompensated HF, who had moderate or severe MR, were included in the present study. The volume status and the N-terminal pro-B-type natriuretic peptide (proBNP) levels were recorded and the echocardiographic parameters were assessed. After the conventional treatment for HF, the proBNP levels and the echocardiographic parameters were assessed again.

Results

The mean age of the patients was 72 ± 9 years and the average hospitalization time was 10.9 ± 5.9 days. Between the beginning and the end of the treatment, there were significant reductions in the effective regurgitant orifice area (EROA) (0.36 ± 0.09 cm² to 0.29 ± 0.09 cm², P < 0.001), vena contracta (VC) (P < 0.001), the regurgitant volume (RV) (P < 0.001), and systolic pulmonary artery pressure (sPAP) (P < 0.001).

Conclusion

This is the first study to investigate the relationship of changes in severity of MR with volume-load by monitoring the proBNP levels among patients with HF. The present results demonstrated that volume reduction, as evidenced by a decline in the proBNP levels, was accompanied by a marked reduction in the EROA, VC, and the RV among patients with left ventricular dysfunction.

The effectiveness of inodilators in reducing short term mortality among patient with severe cardiogenic shock: a propensity-based analysis

Background

The best catecholamine regimen for cardiogenic shock has been poorly evaluated. When a vasopressor is required to treat patients with the most severe form of cardiogenic shock, whether inodilators should be added or whether inopressors can be used alone has not been established. The purpose of this study was to compare the impact of these two strategies on short-term mortality in patients with severe cardiogenic shocks.

Methods and Results

Three observational cohorts of patients with decompensated heart failure were pooled to comprise a total of 1,272 patients with cardiogenic shocks. Of these 1,272 patients, 988 were considered to be severe because they required a vasopressor during the first 24 hours. We developed a propensity-score (PS) model to predict the individual probability of receiving one of the two regimens (inopressors alone or a combination) conditionally on baseline-measured covariates. The benefit of the treatment regimen on the mortality rate was estimated by fitting a weighted Cox regression model. A total of 643 patients (65.1%) died within the first 30 days (inopressors alone: 293 (72.0%); inopressors and inodilators: 350 (60.0%)). After PS weighting, we observed that the use of an inopressor plus an inodilator was associated with an improved short-term mortality (HR: 0.66 [0.55–0.80]) compared to inopressors alone.

Conclusions

In the most severe forms of cardiogenic shock where a vasopressor is immediately required, adding an inodilator may improve short-term mortality. This result should be confirmed in a randomized, controlled trial.

Transthoracic bioimpedance and brain natriuretic peptide levels accurately indicate additional diastolic dysfunction in patients with chronic advanced systolic heart failure

AIMS

Diastolic dysfunction in patients with heart failure has prognostic relevance, possibly because of its relationship with worsening haemodynamic status. In the quest for simpler indexes of haemodynamic status in patients, brain natriuretic peptide (BNP) levels have been proposed as a surrogate of diastolic function. To date, the value of combining BNP levels with non-invasive haemodynamic monitoring by transthoracic electric bioimpedance (TEB) for the prediction of diastolic function has not been evaluated.

METHODS AND RESULTS

We compared left ventricular diastolic function measured by tissue Doppler imaging (TDI) with TEB results and BNP levels in 120 patients with chronic advanced systolic heart failure on optimal treatment (70 +/- 9 years, NYHA 2.4 +/- 0.8, ejection fraction 31 +/- 5%). Of the TEB variables measured, we only considered thoracic fluid content (TFC). To describe diastolic function, we used the TDI of the velocity of displacement of the mitral annulus (E') and the ratio E/E'. In all patients, E/E' was significantly related to TFC and to BNP levels (P < 0.001). Moreover, the combination of BNP > or = 350 pg/mL and TFC > or = 35/kOmega identified patients with diastolic dysfunction (defined as E/E' > or = 15) with high sensitivity and specificity (95 and 94%, respectively).

CONCLUSION

The combination of transthoracic bioimpedance monitoring and BNP measurement accurately indicated the presence of diastolic dysfunction in most patients. These user-friendly and operator-independent tools may be useful as a screening assessment for diastolic dysfunction, and consequently abnormal central haemodynamic status, either in ambulatory patients or when an adequate echocardiographic evaluation is not readily available.

Nitroprusside in decompensated heart failure: what should a clinician really know?

Sodium nitroprusside is an older intravenous vasodilator appropriate for acute hospital treatment of patients with congestive heart failure. It is a balanced arterial and venous vasodilator with a very short half-life, facilitating rapid titration. In general, it improves hemodynamic and clinical status by reducing systemic vascular resistance, left ventricular filling pressure, and increasing cardiac output. This review summarizes recently published literature and recent data regarding the use of this intravenous vasodilator in decompensated heart failure patients.

Effects of levosimendan versus dobutamine on left atrial function in decompensated heart failure

BACKGROUND

Although the effects of levosimendan on the left ventricle (LV) have been studied, its effect on left atrial (LA) function is poorly understood, despite its key role in optimizing LV function.

OBJECTIVE

To compare the effects of levosimendan and dobutamine on LA and LV function in patients with decompensated heart failure (DHF).

METHODS

Seventy-four patients (mean [+/- SD] age 64+/-10 years) with DHF and an LV ejection fraction of 35% or lower were randomly assigned to receive levosimendan (n=37) or dobutamine (n=37). LA active emptying fraction, LA passive emptying fraction (PEF) and the ratio of mitral inflow early diastolic velocity to annulus velocity (E/e) were evaluated with pulsed wave and tissue Doppler imaging along with plasma B-type natriuretic peptide (BNP) level measurements before and after drug infusion.

RESULTS

The ejection fraction was significantly increased in both groups. The levosimendan group had a greater decrease in BNP and a greater increase in active emptying fraction at 24 h compared with the dobutamine group. The PEF, E/e and deceleration time of the E wave were significantly improved in the levosimendan group, but not in the dobutamine group. Levosimendan- induced percentage change of BNP was significantly correlated with the percentage change of E/e and PEF (r=0.48 [P<0.005] and r=-0.38 [P<0.05], respectively).

CONCLUSIONS

In patients with DHF, levosimendan and dobutamine both improve LV systolic function. However, levosimendan also improves LV diastolic function and LA performance in parallel with a greater improvement in neurohormonal activation compared with dobutamine.

Assessing acute ventricular volume changes by intracardiac impedance in a chronic heart failure animal model

BACKGROUND

Implantable device diagnostics may play an essential role in simplifying the care of heart failure patients by providing fundamental insights into their complex clinical patterns. Early recognition of heart failure progression by a continuous hemodynamic monitoring would allow for timely therapeutic interventions to prevent decompensation and hospitalization. In this study, the feasibility of assessing ventricular volume changes by implant-based measurements of intracardiac impedance was tested in a heart failure animal model.

METHODS

Heart failure was induced in five minipigs by high-rate pacing over 3 weeks. During a final open-chest examination a graded dobutamine stress test was performed. Stroke volume (SV) was measured by an ultrasonic flow probe at the ascending aorta. End diastolic pressure (EDP) and maximum pressure slope (dP/dtmax) were calculated from a left ventricular microtip catheter signal. Impedance was measured by an implanted pacemaker between biventricular leads. Stroke impedance (SZ) was calculated as the difference between end-systolic and end-diastolic impedance (EDZ).

RESULTS

Administration of dobutamine led to an increase in SV (55+/-16%), dP/dtmax (107+/-89%), and SZ (56+/-30%). EDP changed by 37+/-21% whereas EDZ changed by 7.4+/-4%. Significant correlations were found between SZ and SV (r=0.88), and between EDZ and EDP (r=-0.82).

CONCLUSION

The strong correlation with SV allows the application of intracardiac impedance measurements for an implant-based continuous monitoring of cardiac function. Impedance may also be used for hemodynamic optimization of cardiac resynchronization therapy.

Left atrial reverse remodeling in dogs with moderate and advanced heart failure treated with a passive mechanical containment device: an echocardiographic study

BACKGROUND

Assessment of global left ventricular (LV) remodeling is important in evaluating the efficacy of pharmacologic and device therapies for the treatment of chronic heart failure (HF). The effects of pharmacologic or device therapies on global left atrial (LA) remodeling in HF, although also important, are not often examined. We showed that long-term therapy with the Acorn Cardiac Support Device (CSD), a passive mechanical ventricular containment device, prevents or reverses LV remodeling in dogs with HF. This study examined the effects of the CSD on global LA remodeling in dogs with moderate and advanced HF.

METHODS AND RESULTS

Studies were performed in 24 dogs with coronary microembolization-induced HF. Of these, 12 had moderate HF (ejection fraction, EF 30% to 40%) and 12 advanced HF (EF < or = 25%). In each group, the CSD was implanted in 6 dogs and the other 6 served as controls. Dogs were followed for 3 months in the moderate group and 6 months in the advanced HF group. LA maximal volume (LAVmax), LA volume at the onset of the p-wave (LAVp), LA minimal volume (LAVmin), LA active emptying volume (LAAEV), and LA active emptying fraction (LAAEF) were measured from 2-dimensional echocardiograms obtained before CSD implantation and at the end of the treatment period. Treatment effect (delta) comparisons between CSD-treated dogs and controls showed that CSD therapy significantly decreased LA volumes (deltaLAVmax: 3.33 +/- 0.70 vs. -2.87 +/- 1.31 mL, P = .002; 7.77 +/- 1.76 versus -0.37 +/- 0.87 mL, P = .002) and improved LA function (deltaLAAEF: -6.00 +/- 1.53 versus 1.85 +/- 1.32%, P = .003; -2.39 +/- 1.10 versus 3.13 +/- 1.66%, P = .02) in the moderate HF and advanced HF groups, respectively.

CONCLUSIONS

Progressive LA enlargement and LA functional deterioration occurs in untreated dogs with HF. Monotherapy with the CSD prevents LA enlargement and improves LA mechanical function in dogs with moderate and advanced HF indicating prevention or reversal of adverse LA remodeling.

Prevalence, predictors and prognostic value of acute impairment in renal function during intensive unloading therapy in a community population hospitalized for decompensated heart failure

BACKGROUND AND METHODS

Chronic heart failure (CHF) is often associated with impaired renal function. Diuretics and vasodilators may lead to aggravated renal dysfunction (ARD), particularly among patients with decompensated CHF. Although the prevalence of ARD has been evaluated in patients awaiting heart transplantation, little is known about ARD in the community sample of CHF patients. Accordingly, we prospectively assessed the prevalence, predictors and prognostic value of ARD in 79 consecutive patients admitted to our general community hospital for decompensated CHF undergoing intensive unloading therapy (intravenous nitroprusside and furosemide). ARD was defined as a >or= 25% increase in serum creatinine between admission and maximal value of >or= 2 mg/dl.

RESULTS

Sixteen patients (20%) developed ARD with a mean increase in serum creatinine of 31% (from 1.74 +/- 0.6 to 2.27 +/- 0.9 mg/dl). ARD persisted at 8-day evaluation in seven of 16 subjects (44%) whereas it was reversible in nine (56%). Lower creatinine clearance at baseline [exp beta = 0.93, 95% confidence interval (CI)=0.87-0.99] and the higher dose of furosemide (exp beta=1.02, 95% CI=1.01-1.03) emerged as independent predictors of ARD. During a follow-up of 11 +/- 8 months, death and hospitalization for worsening CHF occurred more frequently in ARD than non-ARD patients (69% versus 17%, P=0.0001; 69% versus 29%, P=0.003, respectively). Persistent ARD was a powerful independent predictor of long-term adverse outcome (odds ratio=11.1; 95% CI=1.12-36.1; P=0.04).

CONCLUSIONS

Intensive unloading therapy is associated with the development of ARD in one-fifth of the community population hospitalized for decompensated CHF. The magnitude of this phenomenon is not greater than that observed in younger selected populations with advanced CHF, and depends on baseline renal function and increased diuretic dosage. ARD persisting after 8 days from starting intensive unloading is a powerful predictor of subsequent worsened clinical outcome.

Operative contractility: A functional concept of the inotropic state

1. Initial unsuccessful attempts to evaluate ventricular function in terms of the 'heart as a pump' led to focusing on the 'heart as a muscle' and to the concept of myocardial contractility. However, no clinically ideal index exists to assess the contractile state. The aim of the present study was to develop a mathematical model to assess cardiac contractility. 2. A tri-axial system was conceived for preload (PL), afterload (AL) and contractility, where stroke volume (SV) was represented as the volume of the tetrahedron. Based on this model, 'operative' contractility ('OperCon') was calculated from the readily measured values of PL, AL and SV. The model was tested retrospectively under a variety of different experimental and clinical conditions, in 71 studies in humans and 29 studies in dogs. A prospective echocardiographic study was performed in 143 consecutive subjects to evaluate the ability of the model to assess contractility when SV and PL were measured volumetrically (mL) or dimensionally (cm). 3. With inotropic interventions, OperCon changes were comparable to those of ejection fraction (EF), velocity of shortening (Vcf) and dP/dt-max. Only with positive inotropic interventions did elastance (Ees) show significantly larger changes. With load manipulations, OperCon showed significantly smaller changes than EF and Ees and comparable changes to Vcf and dP/dt-max. Values of OperCon were similar when AL was represented by systolic blood pressure or wall stress and when volumetric or dimensional values were used. 4. Operative contractility is a reliable, simple and versatile method to assess cardiac contractility.

Left atrial systolic reserve in idiopathic vs. ischaemic-dilated cardiomyopathy

PURPOSE

There are studies indicating more pronounced left atrial (LA) systolic dysfunction at rest in idiopathic (IDDC) than in ischaemic-dilated cardiomyopathy (ISDC). It was hypothesized that the findings would be similar with regards LA systolic reserve.

METHODS

Twenty-six patients with IDDC, 28 with ISDC and 25 normal controls underwent low-dose dobutamine stress echocardiography (5-10 microg kg(-1) min(-1) IV). Left atrial volumes were echocardiographically determined at rest and during stress at the mitral valve opening (maximal, Vmax), electrocardiographic P wave (onset of atrial systole, Vp) and mitral valve closure (minimal, Vmin) from the apical 4- and 2-chamber views (biplane area-length method). Left atrial systolic function was assessed with the LA-active emptying volume (ACTEV) = Vp-Vmin and fraction (ACTEF) = ACTEV/Vp.

RESULTS

Vmax at rest was similar in IDDC and ISDC and greater than in the controls (54.2 +/- 12 vs. 48.5 +/- 18 vs. 27.1 +/- 6.3 cm(3) m(-2), respectively, P < 0.001) and did not change with stress (53.9 +/- 13.8 vs. 46.9 +/- 16.2 vs. 25.8 +/- 5.9 cm(3) m(-2), P < 0.001). The ACTEV at rest was similar in IDDC and ISDC and greater than in the controls (8.6 +/- 3.5 vs. 9.7 +/- 2.9 vs. 6.1 +/- 2.2 cm(3) m(-2) P < 0.01), whereas during the dobutamine infusion it remained unaltered in IDDC (10.8 +/- 4.6 cm(3) m(-2), P = NS vs. rest) and increased in ISDC (11.8 +/- 3.3 cm(3) m(-2), P < 0.05) and the controls (13.1 +/- 3.2 cm(3) m(-2), P < 0.01). The ACTEF was lower in IDDC than ISDC and the controls at rest (20 +/- 10% vs. 33 +/- 8% vs. 36 +/- 10%, P < 0.01). Dobutamine infusion was associated with no significant increase in ACTEF in IDDC (25 +/- 12%, P = NS vs. rest), and with an increase in this variable in ISDC (39 +/- 10%, P < 0.05) and the controls (49 +/- 12%, P < 0.01).

CONCLUSIONS

Dobutamine infusion is associated with an increase in LA ACTEV and fraction in ISDC and no significant change in these indices in IDDC. These findings indicate a reduced LA systolic reserve in IDDC.

Influence of inotropy and chronotropy on the mitral valve sphincter mechanism

BACKGROUND

This study was designed to isolate and quantify the effects of ventricular inotropic and chronotropic state on the normal mitral valve annular sphincter mechanism.

METHODS

Sonomicrometry tansducers were placed around the mitral annulus in six sheep; atrial pacing wires were also placed. One week later, esmolol was titrated to produce a baseline hemodynamic state with a heart rate of 90 bpm; hemodynamic and sonomicrometry data were recorded. Then animals were paced at 120 bpm and 150 bpm; data were recorded at each heart rate. Isoproterenol infusion was titrated to achieve a heart rate, without pacing, of 120 and 150 bpm; again, data were recorded. Annular area was calculated at end diastole (ED) and end systole (ES) for all experiments using sonomicrometry array localization. Analysis of variance was used to assess the independent effects of heart rate and inotropic state on annular area.

RESULTS

Atrial pacing at 120 bpm produced ES and ED annular areas of 777 +/- 150 mm(2) and 748.8 +/- 140.1 mm(2), respectively. At the same heart rate, isoproterenol-treatment resulted in significantly smaller ES and ED areas: 699 +/- 160 mm(2) and 641.9 +/- 156.5 mm(2), respectively. Atrial pacing at 150 bpm produced ES and ED annular areas of 745.2 +/- 131.3 mm(2) and 723.7 +/- 141.3 mm(2), respectively. At the same heart rate, isoproterenol-treatment resulted in significantly smaller ES and ED areas: 652.8 +/- 146.4 mm(2) and 569.7 +/- 155.9 mm(2), respectively.

CONCLUSIONS

The inotropic state of the left ventricle directly affects the mitral valve annular orifice area, independent of heart rate. This inotropic effect on valve size is more pronounced at ED than at ES in the sheep.

Hemodynamic response to intensive unloading therapy (furosemide and nitroprusside) in patients >70 years of age with left ventricular systolic dysfunction and decompensated chronic heart failure

In patients with decompensated chronic congestive heart failure (CHF), intensive unloading therapy allows an acute decrease in ventricular filling pressures and improves long-term prognosis. Because elderly patients do not routinely undergo invasive hemodynamic evaluation, they are generally denied such a pharmacologic approach. We prospectively characterized the acute hemodynamic response to intensive unloading and its prognostic significance in a elderly population with CHF who were hospitalized for cardiac decompensation. Fifty-nine patients aged >70 years with left ventricular systolic dysfunction underwent intensive unloading therapy (furosemide and nitroprusside) tailored to reduce ventricular filling pressures to near-normal levels. The hemodynamic parameters were monitored by Doppler echocardiography. At baseline, left and right ventricular filling pressures were 21 +/- 3 and 10 +/- 3 mm Hg, respectively. Although all patients experienced a relevant improvement in clinical status during hospital stay, a significant reduction of ventricular filling pressures was detected at discharge in only 40 of them (68%) (responders), whereas 19 patients (32%) had a deficient response to therapy (nonresponders). This unfavorable behavior was predicted by the presence of renal dysfunction at admission. During 19-month follow-up, death due to cardiovascular causes occurred in 8 of 40 responders (20%) and in 9 of 19 nonresponders (47%) (p <0.005). Hospitalizations for cardiovascular causes were more frequent in the nonresponders (58% vs 8%, p <0.0001). Thus, a deficient hemodynamic response to intensive unloading treatment is not infrequent in elderly patients with decompensated CHF. This behavior is predicted by renal dysfunction at admission and is associated with poorer outcome.

Echo-Doppler mitral flow monitoring: an operative tool to evaluate day-to-day tolerance to and effectiveness of beta-adrenergic blocking agent therapy in patients with chronic heart failure

OBJECTIVES

The goals of this study were: 1) to assess the predictive value of baseline mitral flow pattern (MFP) and its changes after loading manipulations as regards tolerance to and effectiveness of beta-adrenergic blocking agent treatment in patients with chronic heart failure (CHF); and 2) to analyze the prognostic implications of chronic MFP modifications after beta-blocker treatment.

BACKGROUND

In patients with CHF, carvedilol therapy induces clinical and hemodynamic improvements. Individual management, clinical effectiveness and prognostic implications, however, remain unclear. The MFP changes induced by loading manipulations provide independent prognostic information.

METHODS

Echo-Doppler was performed at baseline and after loading manipulations in 116 consecutive patients with CHF (left ventricular ejection fraction: 25 +/- 7%); 54 patients with a baseline restrictive MFP were given nitroprusside infusion; 62 patients with a baseline nonrestrictive MFP performed passive leg lifting. According to changes in MFP, we identified four groups: 17 with irreversible restrictive MFP (Irr-rMFP), 37 with reversible restrictive MFP (Rev-rMFP), 12 with unstable nonrestrictive MFP (Un-nrMFP) and 50 with stable nonrestrictive MFP (Sta-nrMFP). Carvedilol therapy (44 +/- 27 mg) was administered blind to results of loading maneuvers. After six months, MFP was reassessed and patients reclassified according to chronic MFP changes. During follow-up, tolerance to and effectiveness of treatment and major cardiac events (death, readmission and urgent transplantation) were considered.

RESULTS

Changes of MFP after loading manipulations were more accurate than baseline MFP in predicting both tolerance to (p < 0.01) and effectiveness of (p < 0.05) carvedilol. After 26 +/- 14 months of follow-up, cardiac events had occurred in 23/102 patients (23%). The event rate in patients with chronic Irr-rMFP or Un-nrMFP was markedly higher than it was in those with Rev-rMFP or Sta-nrMFP.

CONCLUSIONS

In our patients, tolerance to and effectiveness of carvedilol was predicted better by echo-Doppler MFP changes after loading manipulations than by baseline MFP. Chronic changes of MFP after therapy are strong predictors of major cardiac events.

Chronic infusion of dobutamine and nitroprusside in patients with end-stage heart failure awaiting heart transplantation: safety and clinical outcome

BACKGROUND

in patients with severe heart failure additional therapeutic support with intravenous inotropic or vasodilator drugs is frequently employed in an attempt to obtain hemodynamic and clinical control. No data comparing the use and efficacy of chronic intravenous inotropic and vasodilator therapy in patients with advanced heart failure are available.

AIMS

we evaluated, in a group of patients with advanced heart failure undergoing chronic infusion with dobutamine or nitroprusside, in addition to optimized oral therapy, (1) the safety of chronic infusion, (2) the efficacy of both drugs in managing unloading therapy and (3) clinical outcome of the two therapeutic strategies.

METHODS

one hundred and thirteen patients receiving optimized oral therapy, in functional class III/IV with symptoms and signs of refractory heart failure and requiring additional pharmacological support with either intravenous dobutamine or nitroprusside were evaluated. Clinical and therapeutic management and clinical outcome of the two groups were considered.

RESULTS

dobutamine was administered for 12 h/day for 20+/-23 days at a dosage of 7+/-3 microg/kg/min to 43 patients. The mean dose of nitroprusside was 0.76+/-0.99 microg/kg/min. The mean duration of use of this drug, administered as a 12-h/day infusion was 22+/-38 days. Nitroprusside infusion allowed greater doses of short-term ACE-inhibitors to be used compared to pre-infusion (ACE-inhibitor dose: 55+/-30 mg/day vs. 127+/-30 mg/day P<0.0001) and during dobutamine infusion (ACE-inhibitor dose: 85+/-47 mg/day vs. 127+/-30 mg/day P<0.002). Nitroprusside unlike dobutamine significantly improved the NYHA functional class. Of the 113 patients, 109 (97%) had a cardiac event during a mean follow-up of 337+/-264 days. Forty-four patients required hospitalization for worsening congestive heart failure, 45/113 (39%) patients died during the follow-up and 27/113 (24%) patients had a heart transplant in status one. Hospitalization, because of worsening heart failure was less frequent in the nitroprusside than in the dobutamine subgroup [29/51 (57%) vs. 19/22 (86%) P<0.02]. The overall mortality was 28% (20/70) in the nitroprusside group and 58% (25/43) in the dobutamine group (odds ratio 0.33 CI 0.16 to 0.73 P<0.006). In the group treated with nitroprusside, heart transplantation in status one was performed in 16/33 patients (48%), while in the dobutamine group this was done in 11/14 patients (78%) (odds ratio 0.25 CI 0.06-1.02 P<0.06). There was a significant reduction in the combined end-point of mortality/heart transplantation in status one in patients treated with nitroprusside compared to those treated with dobutamine (36/70 (51%) vs. 36/43 (84%) - (odds ratio 0.34 CI 0.14-0.80 P<0.01). The incidence of adverse events in the patients treated with nitroprusside was similar to that in those treated with dobutamine (20% vs. 17% P=ns).

CONCLUSIONS

for patients awaiting heart transplantation chronic intermittent nitroprusside infusions are more effective and safer than dobutamine in relieving symptoms, facilitating unloading therapy management and improving survival. Whether chronic intermittent infusion of nitroprusside could represent a feasible medical strategy in out-patients with severe heart failure remains to be investigated.

Mitral ring annuloplasty: an incomplete correction of functional mitral regurgitation associated with left ventricular remodeling

Functional mitral regurgitation (FMR) occurs commonly in patients undergoing left ventricular (LV) remodeling. It is ubiquitous in patients referred to cardiac transplantation for LV systolic dysfunction and predicts a poor prognosis. The LV remodeling that is responsible for FMR is well understood and involves regional LV dysfunction Mitral annular dilatation is present in patients with idiopathic dilated cardiomyopathy but most often absent in patients with ischemic cardiomyopathy. Nonrandomized observations indicate that implantation of a mitral undersized flexible mitral ring reduces the amount of FMR, reverses LV remodeling, and improves symptoms in patients with end-stage cardiomyopathy and severe FMR. Whether a surgical procedure that does not correct the major LV alterations leading to FMR can have long-lasting effects on the amount of FMR and the reversal of LV remodeling remains to be demonstrated in randomized trials.

Beta-blockade therapy in chronic heart failure: diastolic function and mitral regurgitation improvement by carvedilol

BACKGROUND

In patients with chronic heart failure, the use of carvedilol therapy induces clinical and hemodynamic improvement. However, although the benefits of this beta-blocker have been established in patients with chronic heart failure, the mechanisms underlying them and the changes in left ventricular systolic function, diastolic function, and mitral regurgitation during long-term therapy remain unclear.

OBJECTIVE

To identify the clinical and functional effects of carvedilol, focusing on diastolic function and mitral regurgitation variations.

METHODS

Forty-five consecutive patients with chronic heart failure (ejection fraction 24% +/- 7%), 17 with dilated ischemic and 28 with nonischemic cardiomyopathy, were treated with carvedilol (mean dose 44 +/- 30 mg) and matched for clinical (New York Heart Association functional class and heart failure duration) and hemodynamic (cardiac index and pulmonary wedge pressure) characteristics to a control group. Clinical and echocardiographic variables were measured in the 2 groups at baseline and after 6 months and the results compared.

RESULTS

After 6 months of treatment with carvedilol, left ventricular ejection fraction had increased from 24% +/- 7% to 29% +/- 9% (P <.0001); this change was caused by a reduction in end-systolic volume index (106 +/- 41 vs 93 +/- 37 mL/m(2); P <. 0001). Deceleration time of early diastolic filling increased (134 +/- 74 vs 196 +/- 63 ms; P <.0001). Seventeen of the 27 patients with demonstrated improvement of left ventricular diastolic filling moved from having a restrictive filling pattern to having a normal or pseudonormal left ventricular filling pattern. In the control group, no significant changes in deceleration time of early diastolic filling were found (139 +/- 74 vs 132 +/- 45 ms; P = not significant). The effective regurgitant orifice area decreased significantly in the carvedilol group but not in the control group. These changes were associated with a significant reduction of the mitral regurgitant stroke volume in the carvedilol group (50 +/- 25 vs 16 +/- 13 mL; P <.0001) but not in the control group (57 +/- 29 vs 47 +/- 24 mL; P = not significant). These changes of mitral regurgitation were closely associated with significant improvement of forward aortic stroke volume (r = -.57, P <.0001). These findings were not observed in patients in the control group.

CONCLUSIONS

The results of this study show that long-term carvedilol therapy in patients with chronic heart failure was able to prevent or partially reverse progressive left ventricular dilatation. The effects on left ventricular remodeling were associated with a concomitant recovery of diastolic reserve and a decrease of mitral regurgitation, which have been demonstrated to be powerful prognostic predictors in such patients. Overall these findings provide important insights into the pathophysiologic mechanisms by which carvedilol improves the clinical course of patients with chronic heart failure.

Intravenous inotropic agents in the intensive therapy unit: do they really make a difference?

Part of the management of refractory heart failure is treatment aimed at preventing organ damage due to inadequate oxygen delivery, improving hemodynamics, and maximizing cardiac output while maintaining only mildly elevated ventricular filling pressures The aim of this paper is to review the most updated indications on intravenous inotropic agents, and to compare their cardiac and peripheral effects. Finally, clinical implications of their use (alone or in combination) are reviewed.

[Functional mitral regurgitation. Physiopathology and impact of medical therapy and surgical techniques for left ventricle reduction]

Functional mitral regurgitation is frequently observed in the setting of left ventricular dyfunction. This finding is a marker of poor outcome in patients with either ischemic or dilated cardiomyopathy. The mechanism accounting for this phenomenon is an altered balance of tethering versus coapting forces acting on the mitral valves in the failing heart. Tethering forces represent an anomalous tension on the mitral valves due to displacement of mitral valve attachments secondary to increased left ventricular chamber sphericity associated with systolic ventricular dysfunction. On the other hand, coapting forces are weak and unable to counteract the abnormal tension acting on the mitral valve, which restricts closure and leads to regurgitation. Vasodilators and inotropic drugs are effective in the management of functional mitral regurgitation. Although partial left ventriculectomy or Batista's procedure is still investigational, this new technique seems to provide an optimal control of functional mitral regurgitation and improve functional capacity and survival of some patients with heart failure.

The mechanism of decrease in dynamic mitral regurgitation during heart failure treatment: importance of reduction in the regurgitant orifice size

OBJECTIVES

The purpose of this study was to quantify and characterize the regurgitant flow pattern and regurgitant orifice area in patients undergoing therapy for severe heart failure using contemporary echocardiographic techniques.

BACKGROUND

Mitral regurgitation may be dynamic in patients with heart failure and ultimately correlate with outcome in a group of patients.

METHODS

Fourteen patients with severe heart failure felt to require hemodynamic monitoring for the optimization of medical therapy were enrolled. Two-dimensional and Doppler echocardiograms were performed before and following invasively guided therapy. Hemodynamics and standard echocardiographic dimensions were determined as well as regurgitant volume and regurgitant orifice area derived from color M-mode and Doppler measurements.

RESULTS

Invasively guided therapy for heart failure was associated with a reduction in weight, filling pressures of the left and right heart, systemic vascular resistance, and echocardiographic left atrial, left ventricular and mitral annular dimensions. The mitral regurgitant volume decreased from 47+/-27 ml before therapy to 14+/-14 ml after therapy; p < 0.001. While therapy for heart failure markedly attenuated the volume of regurgitation, the pattern of regurgitant flow across the mitral valve was not significantly altered. In contrast, there was no difference in the velocity time integral of the continuous-wave Doppler spectra of mitral regurgitation with therapy (128+/-23 cm to 123+/-25 cm, p = 0.23). In all patients, the regurgitant orifice area decreased with therapy from 0.55+/-0.38 cm2 to 0.21+/-0.20 cm2 (p < 0.001).

CONCLUSIONS

Pharmacologic reduction in filling pressure and systemic vascular resistance leads to a reduction in the dynamic mitral regurgitation of heart failure through a reduction in the regurgitant orifice area but not through a change in the gradient across the mitral valve. Reduction of the regurgitant orifice area is likely related to decreased left ventricular volumes and decreased annular distention.