Valvular heart disease is the most common cardiac problem complicating pregnancy, and pregnancy in most women with heart disease has a favourable maternal and fetal outcome. With the exception of patients with Eisenmenger syndrome, pulmonary vascular obstructive disease, and Marfan syndrome with aortopathy, maternal death during pregnancy in women with heart disease is rare. However, pregnant women with heart disease do remain at risk for other complications including heart failure, arrhythmia, and stroke. Women with congenital heart disease now comprise the majority of pregnant women with heart disease seen at referral centres. The next largest group includes women with rheumatic heart disease. Peripartum cardiomyopathy, though infrequent, will be discussed in view of its unique relation to pregnancy. Two groups of conditions not discussed further are coronary artery disease which is infrequently encountered, and isolated mitral valve prolapse, which generally has an excellent outcome. Hormonally mediated increases in blood volume, red cell mass, and heart rate result in a major increase in cardiac output during pregnancy; cardiac output peaks during the second trimester, and remains constant until term. Gestational hormones, circulating prostaglandins, and the low resistance vascular bed in the placenta result in concomitant decreases in peripheral vascular resistance and blood pressure. During labour and delivery, pain and uterine contractions result in additional increases in cardiac output and blood pressure. Immediately following delivery, relief of caval compression and autotransfusion from the emptied and contracted uterus produce a further increase in cardiac output. Most haemodynamic changes of pregnancy resolve by two weeks postpartum.

Poisoning refers to the development of dose-related adverse effects following exposure to drugs, chemicals, or other xenobiotics. To paraphrase Paracelsus, the dose creates the poison. Although most poisons have predictable dose-related effects, individual responses to a given dose may vary due to inhibition in the presence of other xenobiotics, genetic polymorphism, enzymatic induction, or acquired tolerance. Poisoning may be local (e.g. lungs, skin, eyes) or systemic depending on the route of exposure, the physical and chemical properties of the poison, and its mechanism of action. The reversibility and severity of poisoning also depend on the functional reserve of the target organ or individual which is influenced by preexisting disease and age. The history should include the route, duration, time, and circumstances (surrounding events, location, and intent) of exposure; the amount and name of each chemical, drug, or ingredient involved; the severity of symptoms, time of onset, nature of symptoms; the time and type of first-aid measures given; and the medical and psychiatric history. In most cases, the patient is unaware of exposure, confused, comatose, or unable or unwilling to admit to one. Suspicious circumstances include unexplained sudden disease in a previously healthy person or a group of healthy people; a history of psychiatric problems (especially depression); current changes in health, social relationships, economic status, or the onset of disease during work with chemicals or after ingestion of drink (especially ethanol), food, or medications. When patients become sick soon after arriving from a foreign country or being arrested for criminal activity, “body packing” or “body stuffing” (ingesting or concealing illicit drugs in a body cavity) should be suspected. Relevant information may be available from friends, paramedics, family, police, pharmacists, physicians, and employers, who should be queried regarding the patient’s, behavioral changes, habits, hobbies, available medications, and antecedent events. Patients have to be asked explicitly concerning their prescribed drugs and recreational medication use. Drugs previously considered “illicit” such as cannabinoids are now legal in many places and prescribed for therapeutic purposes. A search of belongings, clothes, and places of discovery may unveil a suicide note or a container of chemicals or drugs. Without an apparent history in a patient clinically suspected to be poisoned, all drugs available anywhere in the patient’s home or belongings should be considered as possible agents, including drugs for pets. The label on chemical products or the imprint code on drugs may be used to identify the potential toxicity of a suspected poison by consulting the manufacturer, a reference text, a computerized database, or a regional poison information center (800-222-1222). However, poisoning can mimic other illnesses, the correct diagnosis can usually be established by the history, physical examination, routine and toxicologic laboratory evaluations, and characteristic clinical course.

ADHF is a heterogeneous clinical syndrome that usually leads to hospitalization due to a combination of interconnected renal dysfunction, cardiac dysfunction, and vascular compliance. Hospitalizations from ADHF are linked to increased morbidity and mortality, with about half of the patients on readmission within six months and short-term cardiac mortality. Importantly, the overall long-term outcome is still poor, combining rates of cardiovascular death, hospitalization for heart failure, myocardial infarction, and stroke. Managing these patients remain a challenge, with an emphasis on end-organ perfusion (coronary and renal), primarily volume control and reduction of vascular resistance.