do they depend on anomalies of the «T wave»?- breaking latest news

I gave birth three months ago and I often have episodes of rapid heartbeats: sometimes even just getting out of bed to go to the bathroom I reach 130 beats/minute. If I walk, they increase further. When I lie down, I sometimes feel pain in the chest, with a feeling of dizziness and fainting. The cardiologist prescribed me a low dose of metoprolol, as I am breastfeeding. I did several electrocardiograms and some showed “non-specific T wave abnormalities”. Could this be the cause of the racing heart?

He answers Massimo Mapelli, Critical and Rehabilitative Cardiology Department, Card. Monzino, Milan (VAI AL FORUM)

My gynecology professor at the university used to repeat that pregnancy represents, for the woman’s cardiovascular system, a real «stress test». Within certain limits, the variation of some cardiovascular parameters (among which the heart rate) during this period is to be considered solely as the physiological response to the increased need of a body that slowly finds itself containing another. In parallel with the belly and kilograms, in fact, these months the heart chambers gradually dilate and the heart beats increase by about 10-20 per minute compared to baseline values, with the aim of providing the adequate flow of nutrients to the fetus. Once the baby is born, however, the causes of the tachycardia they are to be found elsewhere, especially if they go on for months.

Among the forms associated with a symptomatic tachycardia are thyroid hyperfunction, anemia, substance abuse (starting with coffee), fever, dehydration or, even more frequently, prolonged anxious states which in this phase of life tend to be considerably accentuated, if only due to the probable lack of sleep that accompanies the months after childbirth. With a good clinical picture and a simple blood test, a good part of these forms can be excluded, the treatment of which resolves the tachycardia. Much more rarely the rapid heartbeats can hide a pre-existing heart disease (aggravated by pregnancy) or cardiomyopathy again called «peripartum», a potentially very serious event but which was averted in her case by normal echocardiograms. If no specific cause of those mentioned up to now is highlighted, we are faced, by exclusion, with what is defined as «inappropriate sinus tachycardia». It is a benign dysfunction of the electrical system which is responsible for generating impulses at the level of the heart which, for unspecified reasons, discharges at a heart rate that is too high compared to the needs of our body.

In other words, from a beat point of view, the heart behaves as if we were in the middle of a marathon even while we are simply lying on a sofa, thus generating a subjective sensation of discomfort which can be accompanied by palpitations, shortness of breath or atypical chest pains. In these cases a simple 24-hour electrocardiographic monitoring (Holter) helps to make the diagnosis and guide the therapy. In the particularly symptomatic forms, in fact, it is possible to set up with benefit treatment with beta blockers (such as metoprolol) or, even better, with very selective drugs that act only on the heart rate (ivabradine), to be started only after the breastfeeding period. The famous «nonspecific T wave abnormalities» are an expression used (and abused) by many cardiologists to indicate modest alterations (absolutely not worrying), which appear on the electrocardiographic tracing, more frequently in women.