A Rare Case of Lipomatous Hypertrophy of the Interventricular Septum

Asymmetrical left ventricular hypertrophy secondary to interventricular septum hypertrophy is usually considered a typical phenotype of hypertrophic cardiomyopathy. In rare cases other conditions such as tumors or lipomatous hypertrophy of the interventricular septum may have a similar presentation. We present a case of a male patient who presented for routine cardiology work up and was diagnosed of having ventricular septal hypertrophy secondary to localized lipomatous hypertrophy.

Clinical significance of tissue Doppler imaging in patients with hypertrophic cardiomyopathy

BACKGROUND

A transmitral E/septal Ea ratio > or =15 is a predictor of adverse outcome in cardiac disease, so it was hypothesized that a septal E/Ea >/=15 would predict the risk of adverse outcome, including sustained ventricular tachycardia (VT), cardiac arrest, implantable cardioverter defibrillator (ICD) discharge, or sudden death (SD) in patients with hypertrophic cardiomyopathy (HCM).

METHODS AND RESULTS

The study group comprised 96 consecutive patients with HCM (median age 53 years) who completed all noninvasive tests for risk stratification. The endpoint of the study was defined as death, cardiac arrest, documented sustained VT, or ICD-discharge. The median follow-up was 20.6 months. All patients were alive at the end of follow-up, although 8 patients had reached the endpoint during the study period. The variables that were predictive of adverse clinical outcome were family history of premature SD (p=0.03), syncope (p<0.001), maximum wall thickness > or =3 cm (p=0.02), and septal E/Ea > or =15 (p<0.001). In a stepwise multivariable model the only independent prognostic indicator was a septal E/Ea > or =15 (relative risk 0.26, 95% confidence interval 0.2-0.58, p<0.001). The cumulative event-free survival rate was 78.9% in patients with septal E/Ea > or =15, and 100% in patients with septal E/Ea <15 (p=0.0003).

CONCLUSIONS

Septal E/Ea > or =15 predicts patients with HCM who are at risk of sustained VT, cardiac arrest, ICD-discharge, or SD. (Circ J 2007; 71: 897 - 903).

Left ventricular diastolic dysfunction in idiopathic pulmonary fibrosis: a tissue Doppler echocardiographic [corrected] study

It was hypothesised that, apart from right ventricular (RV) dysfunction, patients with idiopathic pulmonary fibrosis (IPF) also exhibit left ventricular (LV) impairment, which may affect disease progression and prognosis. The aim of the present study was to evaluate LV performance in a cohort of IPF patients using conventional and tissue Doppler ECG. IPF patients exhibiting mild-to-moderate pulmonary arterial hypertension (mean age 65+/-9 yrs; n = 22) and healthy individuals (mean age 61+/-6 yrs; n = 22) were studied. Conventional and tissue Doppler ECG were used for the evaluation of RV and LV systolic and diastolic function. In addition to the expected impairment in RV function, all patients showed a characteristic reversal of LV diastolic filling to late diastole compared with controls (early diastolic peak filling velocity (E)/late diastolic peak filling velocity 0.7+/-0.2 versus 1.5+/-0.1, respectively). Patients with IPF also exhibited lower peak myocardial velocities in early diastole (E(m); 5.7+/-1.1 versus 10.3+/-1.6 cm x s(-1), respectively), higher in late diastole (A(m); 8.9+/-1.3 versus 5.5+/-0.8 cm x s(-1), respectively), lower E(m)/A(m) ratio (0.6+/-0.1 versus 1.9+/-0.5, respectively) and higher E/E(m) ratio (10.8+/-3 versus 6+/-0.6, respectively), all indicative of LV diastolic dysfunction. Moreover, LV propagation velocity was significantly lower in IPF patients (46+/-13 versus 83+/-21 cm x s(-1), respectively). Physicians should be aware that patients with idiopathic pulmonary fibrosis exhibit early impairment of left ventricular diastolic function.

Aortic elastic properties are related to left ventricular diastolic function in patients with type 1 diabetes mellitus

OBJECTIVE

The aim of the study was to evaluate left ventricular diastolic function and its relation to aortic wall stiffness in patients with type 1 diabetes mellitus without coronary artery disease or hypertension.

PATIENTS

Sixty-six patients with type 1 diabetes mellitus were examined by echocardiography and divided into two groups according to the diastolic filling pattern determined by mitral annulus tissue Doppler velocities. Group A patients (n = 21) presented diastolic dysfunction with a peak early diastolic mitral annular velocity (Em)/peak late diastolic mitral annular velocity (Am) ratio <1 whereas in group B patients (n = 45) the Em/Am ratio was >1. Coronary artery disease was excluded based on normal thallium scintigraphy. Aortic stiffness index was calculated from aortic diameters measured by echocardiography, using accepted criteria.

RESULTS

Aortic stiffness index differed significantly among the two groups. Significant correlations were found between parameters of left ventricular diastolic function (Em/Am, isovolumic relaxation time, deceleration time) and aortic stiffness index. Multiple stepwise linear regression analysis revealed aortic stiffness index (beta = -0.39, p = 0.001) and isovolumic relaxation time (beta = -0.46, p < 0.001) as the main predictors of Em/Am ratio.

CONCLUSIONS

Aortic stiffness is increased in type 1 diabetic patients with left ventricular diastolic dysfunction. This impairment in aortic elastic properties seems to be related to parameters of diastolic function.

Utility of tissue Doppler imaging in predicting outcome in patients with idiopathic pulmonary fibrosis

BACKGROUND

There are limited reports in the literature concerning right ventricular (RV) performance in patients with non end-stage idiopathic pulmonary fibrosis (IPF) who exhibit mild to moderate pulmonary hypertension (PH). We evaluated RV functional impairment in such a cohort using both conventional echocardiography and tissue Doppler imaging (TDI) and in addition we assessed the association of specific TDI indices with survival.

METHODS

Twenty-two clinically stable patients with non-end stage IPF and mild to moderate PH were assessed. Twenty-two healthy individuals served as controls. We evaluated RV systolic and diastolic function and further estimated peak pulmonary artery systolic pressure (PASP). In addition, by combining TDI and Doppler echocardiography, we calculated the ratio of trans-tricuspid E-wave velocity to early diastolic tricuspid annulus velocity (RV E/Em). Patients were followed for a median period of 22 months and the incidence of death was recorded.

RESULTS

Both echocardiographic modalities revealed impaired RV systolic and diastolic function in the IPF group compared to controls. A significant negative correlation was observed between RV E/Em and PASP (r = -0.5, p = 0.018). The probability of survival was 54.5% for those patients with RV E/Em < 4.7 versus 100% for those with an index > 4.7 (log-rank statistic 5.81, p = 0.016).

CONCLUSIONS

TDI modality may serve as an alternative to conventional ultrasound technique for risk stratification and PH estimation in non end-stage IPF patients.

Subaortic and midventricular obstructive hypertrophic cardiomyopathy with extreme segmental hypertrophy

Background

Subaortic and midventricular hypertrophic cardiomyopathy in a patient with extreme segmental hypertrophy exceeding the usual maximum wall thickness reported in the literature is a rare phenomenon.

Case Presentation

A 19-year-old man with recently diagnosed hypertrophic cardiomyopathy (HCM) was referred for sudden death risk assessment. The patient had mild exertional dyspnea (New York Heart Association functional class II), but without syncope or chest pain. There was no family history of HCM or sudden death. A two dimensional echocardiogram revealed an asymmetric type of LV hypertrophy; anterior ventricular septum = 49 mm; posterior ventricular septum = 20 mm; anterolateral free wall = 12 mm; and posterior free wall = 6 mm. The patient had 2 types of obstruction; a LV outflow obstruction due to systolic anterior motion of both mitral leaflets (Doppler-estimated 38 mm Hg gradient at rest); and a midventricular obstruction (Doppler-estimated 43 mm Hg gradient), but without apical aneurysm or dyskinesia. The patient had a normal blood pressure response on exercise test and no episodes of non-sustained ventricular tachycardia in 24-h ECG recording. Cardiac MRI showed a gross late enhancement at the hypertrophied septum. Based on the extreme degree of LV hypertrophy and the myocardial hyperenhancement, an implantation of a cardioverter-defibrillator was recommended prophylactically for primary prevention of sudden death.

Conclusion

Midventricular HCM is an infrequent phenotype, but may be associated with an apical aneurysm and progression to systolic dysfunction (end-stage HCM).

Usefulness of colour tissue Doppler imaging in assessing aortic elastic properties in Type 1 diabetic patients

AIMS

Diabetes mellitus (DM) is associated with macrovascular disease and impaired aortic function. We hypothesized that the change in aortic elastic properties could be investigated with colour tissue Doppler imaging (CTDI) in Type 1 diabetic patients and that these findings could be related to the aortic stiffness index.

METHODS

We examined by echocardiography 66 patients with Type 1 DM (mean age 35 +/- 10 years, mean duration of disease 20 +/- 9 years) without a history of arterial hypertension or coronary artery disease (negative thallium-201 stress test) and 66 age- and sex-matched normal subjects. Arterial pressure was measured before echocardiography was performed. Internal aortic systolic and diastolic diameters by M-mode echocardiography and aortic systolic upper wall tissue velocity (Sao, cm/s) by CTDI were measured 3 cm above the aortic valve. Aortic distensibility and aortic stiffness index were calculated using accepted formulae.

RESULTS

Aortic stiffness, distensibility and Sao velocity differed significantly between the studied groups. In the diabetic group, duration of diabetes correlated with aortic stiffness (r = 0.53, P < 0.001), distensibility (r = -0.61, P < 0.001) and Sao velocity (r = -0.48, P < 0.001). There was a negative correlation between aortic stiffness and Sao velocity (r = -0.49, P < 0.001). Multiple stepwise linear regression analysis in the diabetic group revealed that aortic S velocity (beta = 0.30, P = 0.005) and duration of diabetes (beta = -0.49, P = 0.001) were the main predictors of aortic distensibility (overall R(2) = 0.48).

CONCLUSIONS

Aortic elastic properties can be directly assessed by measuring the movements in the upper aortic wall. Reduced aortic S velocity is associated with increased aortic stiffness in Type 1 diabetic patients.

Improved Papillary Muscle Function Attenuates Functional Mitral Regurgitation in Patients with Dilated Cardiomyopathy After Cardiac Resynchronization Therapy

BACKGROUND

Functional mitral valve regurgitation attenuation after cardiac resynchronization therapy (CRT) in patients with severe heart failure has been attributed to both the increased rate of left ventricular systolic pressure increase and to papillary muscle (PM) recoordinated contraction. We hypothesized that an increase in systolic deformation of the PMs or the adjacent myocardial wall may in part account for this effect, by preventing their outward displacement during systole.

METHODS

We studied by echocardiography 22 patients with moderate/severe functional mitral valve regurgitation and a mean ejection fraction of 18 +/- 4% at baseline and after implantation of a CRT system.

RESULTS

CRT induced a significant reduction of the effective regurgitant orifice area (0.18 +/- 0.11 vs 0.35 +/- 0.17 mm2, P < .001). Strain improved in both PMs and their adjacent walls, although this improvement was significant only in anterolateral PM (-16 +/- 4.7 vs -11 +/- 4.3%, P = .02) and posteromedial PM adjacent wall (-16 +/- 10 vs -8 +/- 4.6%, P = .01).

CONCLUSIONS

CRT acutely reduces the severity of functional mitral valve regurgitation in patients with heart failure and this effect may be in part attributed to improved strain of PM or adjacent wall.

Similar pattern of diastolic function adaptation of both ventricles to programmed atrioventricular interval modification in patients with DDD pacing

OBJECTIVE

To evaluate both left ventricular (LV) and right ventricular (RV) diastolic performance adaptation to variable atrioventricular interval (AVI), in patients with DDD pacing for complete heart block and to investigate a possible interaction between LV and RV in this specific cohort of patients.

METHODS

We studied 22 consecutive patients (mean age 65.2 +/- 14.3 years) who underwent DDD pacemaker implantation following admission for complete heart block. One day following implantation, patients were paced at 3 different pacing modes, under the same programmed heart rate and a different AVI (100, 150 and 200 ms respectively). Standard Doppler echocardiography of mitral and tricuspid valve inflow was performed to evaluate LV and RV diastolic function, during each pacing mode.

RESULTS

Left ventricular and RV diastolic performance adaptation to variable AVI modifications was similar, showing a progressive increase of late diastolic filling velocities and a subsequent decrease of E/A wave ratios following AVI prolongation. A short AVI of 100 or 150 ms was associated with improved LV and RV diastolic filling dynamics.

CONCLUSIONS

In elderly patients with complete heart block and unimpaired systolic function undergoing DDD pacemaker implantation, both ventricles share a similar pattern of diastolic function adaptation to AVI modifications and that might be the reflection of ventricular interaction under this specific pacing mode.

Multiple episodes of ischemic preconditioning are not associated with loss of benefit: preliminary clinical experience

BACKGROUND

As a clinical analogue of ischemic preconditioning (IP), preinfarction angina (PA) shares a well-documented protective effect in the setting of acute myocardial infarction (AMI) by reducing infarct size, preserving left ventricular function and improving prognosis. In the experimental setting, multiple cycles of IP may induce the loss of this protection.

OBJECTIVE

To evaluate the effect of repeated cycles of PA on clinical outcomes in patients exhibiting a first AMI.

METHODS

Seventy-four consecutive patients with AMI, in whom PA was the surrogate of experimental IP, were studied prospectively. All patients had poor or no collaterals. The patients were divided into three groups: group 1 (n=32) comprised patients without PA (control subjects); groups 2 (n=24) and 3 (n=18) comprised patients reporting one to four and more than four episodes of new-onset PA, respectively (preconditioned groups). Both of the preconditioned groups were compared with the control subjects with regard to creatine kinase-MB release, corrected Q-T interval (QTc) at discharge and major in-hospital complications.

RESULTS

Compared with the control subjects, groups 2 and 3 exhibited reduced creatine kinase-MB release (75+/-26 IU/L and 85+/-22 IU/L versus 172+/-13 IU/L, P=0.004 and P=0.024, respectively), lower discharge QTc values (418+/-15 ms and 422+/-19 ms versus 443+/-38 ms, P=0.004 and P=0.031, respectively), and a reduced incidence of postinfarction angina (25% and 11% versus 44%, P<0.05), arrhythmias (0% and 0% versus 22%, P<0.05) and pulmonary edema (4% and 0% versus 28%, P<0.05).

CONCLUSIONS

Regardless of the number of recurrences, IP seems to be a powerful intervention to reduce infarct size, limit QTc at discharge and improve the outcome in patients with AMI.

QT dispersion is determined by the relative extent of normal, hibernating, and scarred myocardium in patients with chronic ischemic cardiomyopathy. A dobutamine stress echocardiography study before and after surgical revascularization

INTRODUCTION

The aim of the present study was to evaluate a possible association between QT dispersion (QTd) and the amount of viable and scarred myocardial tissue after revascularization in patients with coronary artery disease and impaired left ventricular (LV) function.

METHODS

Twenty-two patients with ischemic LV dysfunction underwent dobutamine stress echocardiography (DSE) before and 6 months after surgical revascularization. Mean corrected QT-interval value and QTd were calculated at baseline and follow-up. Segments consisting of transmural scar were determined as the segments that remained akinetic in all stages of DSE despite reperfusion. Patients were divided into 2 groups according to the number of definitive segments consisting of transmural scar (minor scar group, < or =2 scarred segments; major scar group, >2 scarred segments).

RESULTS

QTd was significantly lower in the minor compared with the major scar group at baseline and follow-up (mean [SD], 61 [22] vs 98 [33] milliseconds, P = .008, and 45 [18] vs 68 [21] milliseconds, P = .01, respectively). Segments consisting of transmural scar positively correlated to QTd at baseline (r = 0.53, P = .01) and follow-up (r = 0.62, P = .002).

CONCLUSIONS

QTd is positively correlated with the extent of scarred myocardial tissue assessed by DSE. Surgical revascularization results in reduction of QTd in all patients with hibernating myocardium and LV dysfunction.

Effects of variation of atrioventricular interval on left ventricular diastolic filling dynamics and atrial natriuretic peptide levels in patients with DDD pacing for complete heart block

AIMS

This study was designed to evaluate the effect of variation of atrioventricular (AV) interval (AVI) on left ventricular (LV) diastolic function and ANP and c-GMP levels during DDD pacing in patients with complete AV block and normal systolic function.

METHODS

The study population comprised 22 patients (mean age 65.2+/-14.3, 12 males) with complete AV block. All patients underwent complete Doppler echocardiography before implantation of a DDD-pacemaker. Twenty-four hours later, patients were paced for a period of 30 min, at three different AVIs (100 ms, 150 ms and 200 ms), at rest. During each pacing period, Doppler-derived LV diastolic indices were re-evaluated and ANP and c-GMP levels were reassessed.

RESULTS

Overall comparison showed a significant progressive augmentation, from 200 ms to 100 ms AVI, in transmitral E/A wave ratio (from 0.53+/-0.13 to 0.90+/-0.25, P = 0.0005) and in LV filling time (from 0.33+/-0.05 to 0.40+/-0.06s, P = 0.0005), followed by a significant progressive reduction in ANP and c-GMP levels. An AVI of 100 ms or 150 ms was associated with improved diastolic indices and lower natriuretic peptides levels, compared with the longer AVI.

CONCLUSION

Programmed AVI during DDD pacing affects LV diastolic performance and plasma ANP and c-GMP levels. The assessment of these parameters constitutes a useful modality for AVI optimization.

Usefulness of low-dose dobutamine stress echocardiography for the evaluation of spontaneous recovery of stunned myocardium in patients with acute right ventricular infarction

Right ventricular (RV) infarction (RVI) is usually associated with severe RV global dysfunction representing predominantly stunned myocardium that may respond favorably to reperfusion. We assessed the efficacy of low-dose dobutamine stress echocardiography (DSE), performed early in the course of a reperfused RVI, to predict the recovery of RV systolic and diastolic function in 3 months, documenting the recovery of stunned myocardium. In all, 27 patients with acute, successfully thrombolyzed RVI comprised the study population. All patients underwent standard echocardiography at baseline and 3 months later for evaluation of RV systolic and diastolic function. At day 5 DSE was performed for evaluation of RV contractile reserve. Of the total number of segments analyzed, 69% were detected as stunned. At baseline, RV systolic and diastolic indices were seriously impaired showing significant improvement at follow-up. RV wall-motion score index during DSE was positively correlated with the same index at follow-up. DSE is a safe and precise modality to predict recovery of stunned myocardium in the setting of RVI.

Echocardiographic evaluation of spontaneous recovery of right ventricular systolic and diastolic function in patients with acute right ventricular infarction associated with posterior wall left ventricular infarction

We evaluated right ventricular (RV) systolic and diastolic function in 30 patients with acute RV myocardial infarction on echocardiography. Systolic and diastolic function were impaired early in the setting of RV myocardial infarction, but improved significantly at 3 months.

Preconditioning reduces QTc value in patients with first non-ST-segment elevation myocardial infarction (NSTEMI)

BACKGROUND

Preinfarction angina (PA) consists a strong clinical correlate to ischemic preconditioning (PC) and seems to occur in a bimodal time course. The aim of the study is to evaluate the impact of both forms of PC on QTc value representing myocardial electric stability, in patients with a first NSTEMI.

METHODS

Forty-eight patients, with first NSTEMI and poor or no collateral development were enrolled in the study. QTc at admission and discharge were recorded. All patients had comparable admission QTc values and were divided into three groups according to the absence or presence and exact timing of preinfarction angina. The first group consisted of 20 patients who did not report PA (PA-, representing no PC effect); the second group of 12 patients with reported PA within 12 hours prior to admission (12h PA+, representing the classic form of PC); and the third group of 16 patients reporting PA within 12 to 48 hours prior to admission (48-hour PA+, representing the delayed form of PC). The primary outcome was determined as the effect of PA on QTc value at discharge.

RESULTS

Discharge QTc values were significantly reduced in both (PA+) groups compared to (PA-) group (412 +/- 50 vs. 455 +/- 53 ms, p = 0.015 and 417 +/- 29 vs. 455 +/- 53 ms, P = 0.033, respectively). Both groups of (PA+) patients compared to (PA-) patients suffered no arrhythmic events during their hospitalization (0/12 vs. 6/20, P = 0.04 and 0/16 vs. 6/20, P = 0.02).

CONCLUSIONS

Both forms of preconditioning, similarly and significantly reduce QTc value at discharge in patients experiencing a first NSTEMI, suggesting possible protection from future arrhythmic events.

Association between plasma homocysteine levels and coronary artery disease: a population-based study in northern Greece

OBJECTIVE

Elevated plasma total homocysteine (tHcy) levels constitute a risk factor for coronary artery disease (CAD). We prospectively examined the association of fasting tHcy levels in patients in Northern Greece who had established CAD.

PATIENTS AND METHODS

Plasma fasting tHcy levels were measured in 42 patients with angiographically documented CAD and compared to 42 age-, sex-, BMI- and smoking habit-matched control subjects. We also determined the plasma vitamin B(12), folic acid and lipoprotein levels in all patients and controls. Conventional risk factors for CAD were also estimated.

RESULTS

In a univariate analysis, tHcy (micromol/l) levels were higher in patients compared to controls almost reaching statistical significance (13 (7-41) vs 11.3 (4-39); p= 0.07). Multivariate analysis of conventional risk factors showed that tHcy levels were not an independent risk factor for CAD. However, tHcy levels were significantly higher in patients with a previous history of myocardial infarction compared to patients without such a history and to controls (15 (8.8-29) vs 11.7 (7-41); p = 0.007 and 15 (8.8-29) vs 11.3 (4-39); p = 0.002, respectively). Hyperhomocysteinaemia (> 15 micromol/l) was detected in 35.7% of patients and 11.9% of controls (p < 0.05).

CONCLUSIONS

In Northern Greece, plasma tHcy levels may not be an independent risk factor for CAD in patients with angiographically documented CAD. However, patients with CAD have a trend towards higher tHcy levels. Additionally, plasma tHcy levels may be associated with the development of myocardial infarction.

Evidence of ischemic preconditioning in patients experiencing first non-ST-segment elevation myocardial infarction (NSTEMI)

BACKGROUND

Several studies have demonstrated the protective effects of preinfarction angina in Q wave myocardial infarction, implicating the role of ischemic preconditioning but this role remains uncertain in patients with a NSTEMI. Subendocardial viability in NSTEMI patients, is thought to be less dependent on collateral circulation and thus more likely to be protected by other mechanisms such as preconditioning.

METHODS

We have studied prospectively 40 patients with first NSTEMI and with angiographically proven poor or no collateral development and compared two groups; those with versus those without preinfarction angina. All in-hospital events, such as recurrent angina, congestive heart failure, arrhythmias and reinfarction were recorded. Serum markers of myocardial necrosis (CPK, CPK-MB, AST) and discharge QTc values were estimated.

RESULTS

Preconditioned patients suffered less recurrent angina (18 vs. 55% P=0.014), congestive heart failure (0 vs. 22%, P=0.02), arrhythmic events (0 vs. 27%, P=0.008) and had significant smaller values of mean peak CPK (381 +/- 152 vs. 859 +/- 496 I.U./l, P=0.0008), mean peak CPK-MB (45.5 +/- 24.6 vs. 105.2 +/- 87 I.U./l, P=0.01), mean peak AST (59.8 +/- 23.1 vs. 112.4 +/- 64.3 I.U./l, P=0.003) and QTc value at discharge (0.42 +/- 0.03 vs. 0.46 +/- 0.05 s, P=0.005) than patients without preconditioning. Multiple logistic regression analysis confirmed that the absence of preinfarction angina (relative risk 9.10, 95% CI 2.08-40.00, P=0.003) was a significant predictor of in-hospital complications.

CONCLUSIONS

Preinfarction angina constitutes a strong clinical correlate to ischemic preconditioning in patients with first NSTEMI, offering serious protection, by improving in-hospital outcome and reducing infarct size.

In vitro evaluation of the mitogenic effect of platelet-derived growth factor-BB on human periodontal ligament cells cultured with various bone allografts

BACKGROUND

Several studies have documented the role of growth factors in periodontal regeneration. It has been shown that platelet-derived growth factor (PDGF) is a potent stimulator of human periodontal ligament (PDL) cells. A variety of bone graft materials are used to treat osseous defects caused by periodontal disease. We evaluated the mitogenic effect of PDGF on human PDL cells cultured with different allografts to determine which of the allografts with or without PDGF promoted periodontal regeneration.

METHODS

Two human demineralized freeze-dried allografts of cortical (DFDBA) and cancellous (DFBA) bone and a non-demineralized freeze-dried allograft (FBA) from cancellous bone were used alone or supplemented with PDGF-BB. Human PDL cultures were derived from the mid-root of 2 maxillary premolars extracted for orthodontic reasons. Cells were grown separately in 24-well dishes with or without 20 mg of each bone allograft. On day 2 of quiescence, new medium was added with 10 ng/ml of PDGF-BB. DNA synthesis was estimated by measuring [3H] thymidine incorporation to determine the effects of the test agents on cell proliferation. Cells were processed and subjected to scintillation counting after 48 hours of incubation. Counts per minute (cpm/well) were determined for each sample.

RESULTS

There was no statistically significant difference (P<0.05) on PDL cell proliferation when the allografts were used alone. PDL cells exhibited significantly greater proliferative responses to the 2 demineralized bone allografts, DFDBA and DFBA, when combined with PDGF-BB. A statistically significant difference on DNA synthesis was noticed when PDGF-BB was added to PDL cells cultured with FBA. PDL cells displayed no significant increase in mitogenic activity when cultured with PDGF-BB alone.

CONCLUSIONS

The findings of this study demonstrate the beneficial role of DFDBA, DFBA, and FBA as synergic agents with PDGF-BB to periodontal regeneration. The significant ability of the 2 decalcified bone allografts, DFDBA and DFBA, combined with PDGF to stimulate PDL cell proliferation might be a useful adjunct in the treatment of periodontal defects.