Diabetes ja sydämen vajaatoiminta: uudet lääkkeet herättävät toiveita

Sydämen vajaatoiminnan ja diabeteksen yhdistelmä on vaarallinen ja ilmeisesti kaksisuuntainen: vajaatoiminta lisää insuliiniresistenssiä ja vajaatoimintapotilailla ilmenee tavallista useammin diabetesta. Uudet diabeteslääkkeet herättävät toiveita. Osa niistä saattaa parantaa sydämen vajaatoimintaa sairastavien diabeetikoiden huonoa ennustetta.</p

SGLT2:n estäjät - enemmän kuin diabeteslääke

Natriumin- ja glukoosinkuljettajaproteiini 2:n (SGLT2) estäjät eivät ole vain tavanomaisia suurentunutta verenglukoosipitoisuutta pienentäviä diabeteslääkkeitä. Ne parantavat tyypin 2 diabetespotilaiden ennustetta ja ehkäisevät sydäntapahtumia, jos potilaalla on tiedossa oleva sydäntauti tai merkittävä sydäntautiriski. Ne vähentävät diabetespotilaiden sydämen vajaatoiminnan ilmaantumista ja vaikeutumisvaiheita. Lääkeryhmän hyödyt koskevat myös niitä sydänriskipotilaita, joiden verenglukoosipitoisuus ei pienene hoidon aikana tai joiden glukoositasapaino on hyvä jo ennen lääkkeen aloitusta. SGLT2:n estäjät onkin nostettu eurooppalaisissa hoitosuosituksissa ensilinjan lääkkeeksi hyvin suuren sydän- ja verisuonitautiriskin diabetespotilaille. Koska SGLT2:n estäjät parantavat pumppaustoiminnan heikentymisestä johtuvan sydämen vajaatoiminnan ennustetta ja vähentävät myös diabetesta sairastamattomien potilaiden vajaatoiminnan vaikeutumisvaiheita, niiden käyttö laajenee muihinkin ryhmiin kuin diabetespotilaisiin

How to Optimize Cardioversion of Atrial Fibrillation

Cardioversion (CV) is an essential component of rhythm control strategy in the treatment of atrial fibrillation (AF). Timing of CV is an important manageable factor in optimizing the safety and efficacy of CV. Based on observational studies, the success rate of CV seems to be best (approximate to 95%) at 12-48 h after the onset of arrhythmic symptoms compared with a lower success rate of approximate to 85% in later elective CV. Early AF recurrences are also less common after acute CV compared with later elective CV. CV causes a temporary increase in the risk of thromboembolic complications. Effective anticoagulation reduces this risk, especially during the first 2 weeks after successful CV. However, even during therapeutic anticoagulation, each elective CV increases the risk of stroke 4-fold (0.4% vs. 0.1%) during the first month after the procedure, compared with acute (<48 h) CV or avoiding CV. Spontaneous CVs are common during the early hours of AF. The short wait-and-see approach, up to 24-48 h, is a reasonable option for otherwise healthy but mildly symptomatic patients who are using therapeutic anticoagulation, since they are most likely to have spontaneous rhythm conversion and have no need for active CV. The probability of early treatment failure and antiarrhythmic treatment options should be evaluated before proceeding to CV to avoid the risks of futile CVs

Relation between heart rate variability and spontaneous and induced ventricular arrhythmias in patients with coronary artery disease

AbstractObjectives. The aim of this study was to determine the relation between autonomic control of heart rate and the spontaneous occurrence and inducibility of ventricular arrhythmias in patients with coronary artery disease.Background. Low heart rate variability increases the risk of arrhythmic events. It is not known whether impaired autonomic heart rate control reflects alterations in functional factors that contribute to the initiation of spontaneous arrhythmias or whether it is the consequence of an anatomic substrate for reentrant tachyarrhythmias.Methods. Fifty-four patients with coronary artery disease with a history of sustained ventricular tachycardia (n = 25) or cardiac arrest (n = 29) were studied by 24-h ambulatory electrocardiographic recording and by programmed electrical stimulation. Heart rate variability was compared among the patients with and without spontaneous ventricular arrhythmias and with and without inducibility of sustained ventricular tachyarrhythmias.Results. Eight patients had a total of 21 episodes of sustained ventricular tachycardia on Holter recordings. Standard deviation of RR intervals and low frequency and very low frequency components of heart rate variability were significantly blunted in patients with sustained ventricular tachycardias compared with those without repetitive ventricular ectopic activity (p < 0.05, p < 0.01 and p < 0.05, respectively). However, no significant alterations were observed in heart rate variability before the onset of 21 episodes of sustained ventricular tachycardia. Heart rate variability did not differ between the patients with or without nonsustained episodes of ventricular tachycardia. In patients with frequent ventricular ectopic activity, low frequency and very low frequency power components were significantly blunted compared with those with infrequent ventricular ectopic activity (p < 0.01 and p < 0.001, respectively). Heart rate variability did not differ significantly between the patients with and without inducible sustained ventricular tachyarrhythmias.Conclusions. Impaired very low and low frequency oscillation of heart rate reflects susceptibility to the spontaneous occurrence of ventricular arrhythmias but may not reflect the instantaneous triggers for life-threatening arrhythmias or a specific marker of the arrhythmic substrate for ventricular tachyarrhythmias

Increased B-Type Natriuretic Peptide Concentration Is Associated with Reduced Coronary Vasoreactivity in Patients with Dilated Cardiomyopathy but Not in Healthy Young Subjects

Background/Aims. Natriuretic peptides are associated with the cardiovascular disease risk under a range of different circumstances. However, less is known about whether this association is found also in young healthy subjects. Methods. 9 patients with dilated cardiomyopathy and 26 healthy young subjects were studied. The myocardial blood flow measurements were performed basally and during adenosine infusion using PET. Results. S-proBNP concentrations were significantly higher (2153 ± 1964 versus 28 ± 17 ng/L, P = .000002) and adenosine-stimulated flow lower (1.6 ± 0.8 versus 3.6 ± 1.1 mL·g−1·min−1, P = .00001) in patients with dilated cardiomyopathy when compared to healthy subjects. S-proBNP concentration was inversely associated with adenosine stimulated flow in patients with dilated cardiomyopathy (r = −0.75, P = .019) but not in healthy subjects (r = −0.06, P = .84). Conclusions. Natriuretic peptides are inversely associated with coronary vasoreactivity in patients with dilated cardiomyopathy but not in healthy young subjects. Since reduced coronary vasoreactivity seems to be one of the earliest abnormalities in the development of coronary artery disease, this might indicate that natriuretic peptides are not predictor of cardiovascular disease risk in healthy young subjects