Atrial infarction, inferior myocardial infarction atrial arrhythmia a forgotten triad

Case presentation

ID : LMFB, 66 years old, female, born and living in Pacatuba – Ceará, Brazil.

Main complaint: “chest pain and shortness of breath”
History of current disease: the patient informed about very intense constrictive precordial pain associated to nausea and vomits with delta-T (ΔT) of 4 hours (ΔT is the time of arrival of each patient to the Emergency Department). She informed about dyspnea to great and moderate strain for the last six months, with worsening after the onset of precordial pain.

Personal pathological history: she mentioned high blood pressure and smoker for a long time. Stroke in 2009 with no sequelae. She denied having Diabetes mellitus, dyslipidemia or other risk factor.

Physical examination: oriented, Glasgow scale 15.

CPA: Split, regular heart rhythm, normal sounds, no murmurs. Systemic blood pressure: 169×78 mmHg, Heart Rate: 104 bpm.
Pulmonary auscultation: vesicular murmur present, with no adventitious sounds. Respiratory rate: 29 rpm.
It is decided to treat her with Primary Percutaneous Coronary Intervention (PPCI) and three stents where implanted.

Questions:

1. Which is the “culprit” artery and obstruction location? And why?
2. What is the heart rhythm of the first ECG?
3. What is/are the mechanism(s) of P wave alterations?

Apresentação do caso

ID : L.M.F.B., 66 anos, natural e residente em Pacatuba-CE.

Queixa Principal: “dor no peito e falta de ar”
História da doença atual: paciente refere dor precordial de forte intensidade associada a náuseas e vômitos com delta-T de 4 horas. Relata dispneia aos grandes e moderados esforços há 6 meses com piora após o início da dor precordial.

Antecedentes pessoais patológicos : refere HAS e tabagismo de longa data. AVC em 2009 sem sequelas. Nega DM.

Ex. físico: orientada, Glasgow 15.

ACP: ritmo cardíaco regular, em 2 tempos, bulhas normofonética, sem sopros. PAS 169x78mmHg, FC 104bpm.
Ausculta pulmonar: murmúrio vesicular presente sem ruídos adventícios. Frequência respiratória 29 irpm.
Se decide tartar com angioplastia primaria e se implantam stent na CD

Perguntas:

1. Qual a artéria culpada e local da obstrução? E por quê?
2. Qual o ritmo cardíaco do primeiro ECG?
3. Qual(s) o(s) mecanismo(s) das alterações da onda P?

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